python, hg: tow outside the environment.

they've served us well, and can ride off into the sunset.

1 files changed, 0 insertions, 3279 deletions

diff --git a/sys/src/cmd/python/Modules/parsermodule.c b/sys/src/cmd/python/Modules/parsermodule.c
deleted file mode 100644
index e33197e39..000000000
--- a/sys/src/cmd/python/Modules/parsermodule.c
+++ /dev/null
@@ -1,3279 +0,0 @@
-/*  parsermodule.c
- *
- *  Copyright 1995-1996 by Fred L. Drake, Jr. and Virginia Polytechnic
- *  Institute and State University, Blacksburg, Virginia, USA.
- *  Portions copyright 1991-1995 by Stichting Mathematisch Centrum,
- *  Amsterdam, The Netherlands.  Copying is permitted under the terms
- *  associated with the main Python distribution, with the additional
- *  restriction that this additional notice be included and maintained
- *  on all distributed copies.
- *
- *  This module serves to replace the original parser module written
- *  by Guido.  The functionality is not matched precisely, but the
- *  original may be implemented on top of this.  This is desirable
- *  since the source of the text to be parsed is now divorced from
- *  this interface.
- *
- *  Unlike the prior interface, the ability to give a parse tree
- *  produced by Python code as a tuple to the compiler is enabled by
- *  this module.  See the documentation for more details.
- *
- *  I've added some annotations that help with the lint code-checking
- *  program, but they're not complete by a long shot.  The real errors
- *  that lint detects are gone, but there are still warnings with
- *  Py_[X]DECREF() and Py_[X]INCREF() macros.  The lint annotations
- *  look like "NOTE(...)".
- */
-
-#include "Python.h"                     /* general Python API             */
-#include "graminit.h"                   /* symbols defined in the grammar */
-#include "node.h"                       /* internal parser structure      */
-#include "errcode.h"                    /* error codes for PyNode_*()     */
-#include "token.h"                      /* token definitions              */
-                                        /* ISTERMINAL() / ISNONTERMINAL() */
-#include "compile.h"                    /* PyNode_Compile()               */
-
-#ifdef lint
-#include <note.h>
-#else
-#define NOTE(x)
-#endif
-
-/*  String constants used to initialize module attributes.
- *
- */
-static char parser_copyright_string[] =
-"Copyright 1995-1996 by Virginia Polytechnic Institute & State\n\
-University, Blacksburg, Virginia, USA, and Fred L. Drake, Jr., Reston,\n\
-Virginia, USA.  Portions copyright 1991-1995 by Stichting Mathematisch\n\
-Centrum, Amsterdam, The Netherlands.";
-
-
-PyDoc_STRVAR(parser_doc_string,
-"This is an interface to Python's internal parser.");
-
-static char parser_version_string[] = "0.5";
-
-
-typedef PyObject* (*SeqMaker) (Py_ssize_t length);
-typedef int (*SeqInserter) (PyObject* sequence,
-                            Py_ssize_t index,
-                            PyObject* element);
-
-/*  The function below is copyrighted by Stichting Mathematisch Centrum.  The
- *  original copyright statement is included below, and continues to apply
- *  in full to the function immediately following.  All other material is
- *  original, copyrighted by Fred L. Drake, Jr. and Virginia Polytechnic
- *  Institute and State University.  Changes were made to comply with the
- *  new naming conventions.  Added arguments to provide support for creating
- *  lists as well as tuples, and optionally including the line numbers.
- */
-
-
-static PyObject*
-node2tuple(node *n,                     /* node to convert               */
-           SeqMaker mkseq,              /* create sequence               */
-           SeqInserter addelem,         /* func. to add elem. in seq.    */
-           int lineno)                  /* include line numbers?         */
-{
-    if (n == NULL) {
-        Py_INCREF(Py_None);
-        return (Py_None);
-    }
-    if (ISNONTERMINAL(TYPE(n))) {
-        int i;
-        PyObject *v;
-        PyObject *w;
-
-        v = mkseq(1 + NCH(n) + (TYPE(n) == encoding_decl));
-        if (v == NULL)
-            return (v);
-        w = PyInt_FromLong(TYPE(n));
-        if (w == NULL) {
-            Py_DECREF(v);
-            return ((PyObject*) NULL);
-        }
-        (void) addelem(v, 0, w);
-        for (i = 0; i < NCH(n); i++) {
-            w = node2tuple(CHILD(n, i), mkseq, addelem, lineno);
-            if (w == NULL) {
-                Py_DECREF(v);
-                return ((PyObject*) NULL);
-            }
-            (void) addelem(v, i+1, w);
-        }
-
-        if (TYPE(n) == encoding_decl)
-            (void) addelem(v, i+1, PyString_FromString(STR(n)));
-        return (v);
-    }
-    else if (ISTERMINAL(TYPE(n))) {
-        PyObject *result = mkseq(2 + lineno);
-        if (result != NULL) {
-            (void) addelem(result, 0, PyInt_FromLong(TYPE(n)));
-            (void) addelem(result, 1, PyString_FromString(STR(n)));
-            if (lineno == 1)
-                (void) addelem(result, 2, PyInt_FromLong(n->n_lineno));
-        }
-        return (result);
-    }
-    else {
-        PyErr_SetString(PyExc_SystemError,
-                        "unrecognized parse tree node type");
-        return ((PyObject*) NULL);
-    }
-}
-/*
- *  End of material copyrighted by Stichting Mathematisch Centrum.
- */
-
-
-
-/*  There are two types of intermediate objects we're interested in:
- *  'eval' and 'exec' types.  These constants can be used in the st_type
- *  field of the object type to identify which any given object represents.
- *  These should probably go in an external header to allow other extensions
- *  to use them, but then, we really should be using C++ too.  ;-)
- */
-
-#define PyST_EXPR  1
-#define PyST_SUITE 2
-
-
-/*  These are the internal objects and definitions required to implement the
- *  ST type.  Most of the internal names are more reminiscent of the 'old'
- *  naming style, but the code uses the new naming convention.
- */
-
-static PyObject*
-parser_error = 0;
-
-
-typedef struct {
-    PyObject_HEAD                       /* standard object header           */
-    node* st_node;                      /* the node* returned by the parser */
-    int   st_type;                      /* EXPR or SUITE ?                  */
-} PyST_Object;
-
-
-static void parser_free(PyST_Object *st);
-static int parser_compare(PyST_Object *left, PyST_Object *right);
-static PyObject *parser_getattr(PyObject *self, char *name);
-
-
-static
-PyTypeObject PyST_Type = {
-    PyObject_HEAD_INIT(NULL)
-    0,
-    "parser.st",                        /* tp_name              */
-    (int) sizeof(PyST_Object),          /* tp_basicsize         */
-    0,                                  /* tp_itemsize          */
-    (destructor)parser_free,            /* tp_dealloc           */
-    0,                                  /* tp_print             */
-    parser_getattr,                     /* tp_getattr           */
-    0,                                  /* tp_setattr           */
-    (cmpfunc)parser_compare,            /* tp_compare           */
-    0,                                  /* tp_repr              */
-    0,                                  /* tp_as_number         */
-    0,                                  /* tp_as_sequence       */
-    0,                                  /* tp_as_mapping        */
-    0,                                  /* tp_hash              */
-    0,                                  /* tp_call              */
-    0,                                  /* tp_str               */
-    0,                                  /* tp_getattro          */
-    0,                                  /* tp_setattro          */
-
-    /* Functions to access object as input/output buffer */
-    0,                                  /* tp_as_buffer         */
-
-    Py_TPFLAGS_DEFAULT,                 /* tp_flags             */
-
-    /* __doc__ */
-    "Intermediate representation of a Python parse tree."
-};  /* PyST_Type */
-
-
-static int
-parser_compare_nodes(node *left, node *right)
-{
-    int j;
-
-    if (TYPE(left) < TYPE(right))
-        return (-1);
-
-    if (TYPE(right) < TYPE(left))
-        return (1);
-
-    if (ISTERMINAL(TYPE(left)))
-        return (strcmp(STR(left), STR(right)));
-
-    if (NCH(left) < NCH(right))
-        return (-1);
-
-    if (NCH(right) < NCH(left))
-        return (1);
-
-    for (j = 0; j < NCH(left); ++j) {
-        int v = parser_compare_nodes(CHILD(left, j), CHILD(right, j));
-
-        if (v != 0)
-            return (v);
-    }
-    return (0);
-}
-
-
-/*  int parser_compare(PyST_Object* left, PyST_Object* right)
- *
- *  Comparison function used by the Python operators ==, !=, <, >, <=, >=
- *  This really just wraps a call to parser_compare_nodes() with some easy
- *  checks and protection code.
- *
- */
-static int
-parser_compare(PyST_Object *left, PyST_Object *right)
-{
-    if (left == right)
-        return (0);
-
-    if ((left == 0) || (right == 0))
-        return (-1);
-
-    return (parser_compare_nodes(left->st_node, right->st_node));
-}
-
-
-/*  parser_newstobject(node* st)
- *
- *  Allocates a new Python object representing an ST.  This is simply the
- *  'wrapper' object that holds a node* and allows it to be passed around in
- *  Python code.
- *
- */
-static PyObject*
-parser_newstobject(node *st, int type)
-{
-    PyST_Object* o = PyObject_New(PyST_Object, &PyST_Type);
-
-    if (o != 0) {
-        o->st_node = st;
-        o->st_type = type;
-    }
-    else {
-        PyNode_Free(st);
-    }
-    return ((PyObject*)o);
-}
-
-
-/*  void parser_free(PyST_Object* st)
- *
- *  This is called by a del statement that reduces the reference count to 0.
- *
- */
-static void
-parser_free(PyST_Object *st)
-{
-    PyNode_Free(st->st_node);
-    PyObject_Del(st);
-}
-
-
-/*  parser_st2tuple(PyObject* self, PyObject* args, PyObject* kw)
- *
- *  This provides conversion from a node* to a tuple object that can be
- *  returned to the Python-level caller.  The ST object is not modified.
- *
- */
-static PyObject*
-parser_st2tuple(PyST_Object *self, PyObject *args, PyObject *kw)
-{
-    PyObject *line_option = 0;
-    PyObject *res = 0;
-    int ok;
-
-    static char *keywords[] = {"ast", "line_info", NULL};
-
-    if (self == NULL) {
-        ok = PyArg_ParseTupleAndKeywords(args, kw, "O!|O:st2tuple", keywords,
-                                         &PyST_Type, &self, &line_option);
-    }
-    else
-        ok = PyArg_ParseTupleAndKeywords(args, kw, "|O:totuple", &keywords[1],
-                                         &line_option);
-    if (ok != 0) {
-        int lineno = 0;
-        if (line_option != NULL) {
-            lineno = (PyObject_IsTrue(line_option) != 0) ? 1 : 0;
-        }
-        /*
-         *  Convert ST into a tuple representation.  Use Guido's function,
-         *  since it's known to work already.
-         */
-        res = node2tuple(((PyST_Object*)self)->st_node,
-                         PyTuple_New, PyTuple_SetItem, lineno);
-    }
-    return (res);
-}
-
-
-/*  parser_st2list(PyObject* self, PyObject* args, PyObject* kw)
- *
- *  This provides conversion from a node* to a list object that can be
- *  returned to the Python-level caller.  The ST object is not modified.
- *
- */
-static PyObject*
-parser_st2list(PyST_Object *self, PyObject *args, PyObject *kw)
-{
-    PyObject *line_option = 0;
-    PyObject *res = 0;
-    int ok;
-
-    static char *keywords[] = {"ast", "line_info", NULL};
-
-    if (self == NULL)
-        ok = PyArg_ParseTupleAndKeywords(args, kw, "O!|O:st2list", keywords,
-                                         &PyST_Type, &self, &line_option);
-    else
-        ok = PyArg_ParseTupleAndKeywords(args, kw, "|O:tolist", &keywords[1],
-                                         &line_option);
-    if (ok) {
-        int lineno = 0;
-        if (line_option != 0) {
-            lineno = PyObject_IsTrue(line_option) ? 1 : 0;
-        }
-        /*
-         *  Convert ST into a tuple representation.  Use Guido's function,
-         *  since it's known to work already.
-         */
-        res = node2tuple(self->st_node,
-                         PyList_New, PyList_SetItem, lineno);
-    }
-    return (res);
-}
-
-
-/*  parser_compilest(PyObject* self, PyObject* args)
- *
- *  This function creates code objects from the parse tree represented by
- *  the passed-in data object.  An optional file name is passed in as well.
- *
- */
-static PyObject*
-parser_compilest(PyST_Object *self, PyObject *args, PyObject *kw)
-{
-    PyObject*     res = 0;
-    char*         str = "<syntax-tree>";
-    int ok;
-
-    static char *keywords[] = {"ast", "filename", NULL};
-
-    if (self == NULL)
-        ok = PyArg_ParseTupleAndKeywords(args, kw, "O!|s:compilest", keywords,
-                                         &PyST_Type, &self, &str);
-    else
-        ok = PyArg_ParseTupleAndKeywords(args, kw, "|s:compile", &keywords[1],
-                                         &str);
-
-    if (ok)
-        res = (PyObject *)PyNode_Compile(self->st_node, str);
-
-    return (res);
-}
-
-
-/*  PyObject* parser_isexpr(PyObject* self, PyObject* args)
- *  PyObject* parser_issuite(PyObject* self, PyObject* args)
- *
- *  Checks the passed-in ST object to determine if it is an expression or
- *  a statement suite, respectively.  The return is a Python truth value.
- *
- */
-static PyObject*
-parser_isexpr(PyST_Object *self, PyObject *args, PyObject *kw)
-{
-    PyObject* res = 0;
-    int ok;
-
-    static char *keywords[] = {"ast", NULL};
-
-    if (self == NULL)
-        ok = PyArg_ParseTupleAndKeywords(args, kw, "O!:isexpr", keywords,
-                                         &PyST_Type, &self);
-    else
-        ok = PyArg_ParseTupleAndKeywords(args, kw, ":isexpr", &keywords[1]);
-
-    if (ok) {
-        /* Check to see if the ST represents an expression or not. */
-        res = (self->st_type == PyST_EXPR) ? Py_True : Py_False;
-        Py_INCREF(res);
-    }
-    return (res);
-}
-
-
-static PyObject*
-parser_issuite(PyST_Object *self, PyObject *args, PyObject *kw)
-{
-    PyObject* res = 0;
-    int ok;
-
-    static char *keywords[] = {"ast", NULL};
-
-    if (self == NULL)
-        ok = PyArg_ParseTupleAndKeywords(args, kw, "O!:issuite", keywords,
-                                         &PyST_Type, &self);
-    else
-        ok = PyArg_ParseTupleAndKeywords(args, kw, ":issuite", &keywords[1]);
-
-    if (ok) {
-        /* Check to see if the ST represents an expression or not. */
-        res = (self->st_type == PyST_EXPR) ? Py_False : Py_True;
-        Py_INCREF(res);
-    }
-    return (res);
-}
-
-
-#define PUBLIC_METHOD_TYPE (METH_VARARGS|METH_KEYWORDS)
-
-static PyMethodDef
-parser_methods[] = {
-    {"compile",         (PyCFunction)parser_compilest,  PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Compile this ST object into a code object.")},
-    {"isexpr",          (PyCFunction)parser_isexpr,     PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Determines if this ST object was created from an expression.")},
-    {"issuite",         (PyCFunction)parser_issuite,    PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Determines if this ST object was created from a suite.")},
-    {"tolist",          (PyCFunction)parser_st2list,    PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Creates a list-tree representation of this ST.")},
-    {"totuple",         (PyCFunction)parser_st2tuple,   PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Creates a tuple-tree representation of this ST.")},
-
-    {NULL, NULL, 0, NULL}
-};
-
-
-static PyObject*
-parser_getattr(PyObject *self, char *name)
-{
-    return (Py_FindMethod(parser_methods, self, name));
-}
-
-
-/*  err_string(char* message)
- *
- *  Sets the error string for an exception of type ParserError.
- *
- */
-static void
-err_string(char *message)
-{
-    PyErr_SetString(parser_error, message);
-}
-
-
-/*  PyObject* parser_do_parse(PyObject* args, int type)
- *
- *  Internal function to actually execute the parse and return the result if
- *  successful or set an exception if not.
- *
- */
-static PyObject*
-parser_do_parse(PyObject *args, PyObject *kw, char *argspec, int type)
-{
-    char*     string = 0;
-    PyObject* res    = 0;
-
-    static char *keywords[] = {"source", NULL};
-
-    if (PyArg_ParseTupleAndKeywords(args, kw, argspec, keywords, &string)) {
-        node* n = PyParser_SimpleParseString(string,
-                                             (type == PyST_EXPR)
-                                             ? eval_input : file_input);
-
-	if (n)
-	    res = parser_newstobject(n, type);
-    }
-    return (res);
-}
-
-
-/*  PyObject* parser_expr(PyObject* self, PyObject* args)
- *  PyObject* parser_suite(PyObject* self, PyObject* args)
- *
- *  External interfaces to the parser itself.  Which is called determines if
- *  the parser attempts to recognize an expression ('eval' form) or statement
- *  suite ('exec' form).  The real work is done by parser_do_parse() above.
- *
- */
-static PyObject*
-parser_expr(PyST_Object *self, PyObject *args, PyObject *kw)
-{
-    NOTE(ARGUNUSED(self))
-    return (parser_do_parse(args, kw, "s:expr", PyST_EXPR));
-}
-
-
-static PyObject*
-parser_suite(PyST_Object *self, PyObject *args, PyObject *kw)
-{
-    NOTE(ARGUNUSED(self))
-    return (parser_do_parse(args, kw, "s:suite", PyST_SUITE));
-}
-
-
-
-/*  This is the messy part of the code.  Conversion from a tuple to an ST
- *  object requires that the input tuple be valid without having to rely on
- *  catching an exception from the compiler.  This is done to allow the
- *  compiler itself to remain fast, since most of its input will come from
- *  the parser directly, and therefore be known to be syntactically correct.
- *  This validation is done to ensure that we don't core dump the compile
- *  phase, returning an exception instead.
- *
- *  Two aspects can be broken out in this code:  creating a node tree from
- *  the tuple passed in, and verifying that it is indeed valid.  It may be
- *  advantageous to expand the number of ST types to include funcdefs and
- *  lambdadefs to take advantage of the optimizer, recognizing those STs
- *  here.  They are not necessary, and not quite as useful in a raw form.
- *  For now, let's get expressions and suites working reliably.
- */
-
-
-static node* build_node_tree(PyObject *tuple);
-static int   validate_expr_tree(node *tree);
-static int   validate_file_input(node *tree);
-static int   validate_encoding_decl(node *tree);
-
-/*  PyObject* parser_tuple2st(PyObject* self, PyObject* args)
- *
- *  This is the public function, called from the Python code.  It receives a
- *  single tuple object from the caller, and creates an ST object if the
- *  tuple can be validated.  It does this by checking the first code of the
- *  tuple, and, if acceptable, builds the internal representation.  If this
- *  step succeeds, the internal representation is validated as fully as
- *  possible with the various validate_*() routines defined below.
- *
- *  This function must be changed if support is to be added for PyST_FRAGMENT
- *  ST objects.
- *
- */
-static PyObject*
-parser_tuple2st(PyST_Object *self, PyObject *args, PyObject *kw)
-{
-    NOTE(ARGUNUSED(self))
-    PyObject *st = 0;
-    PyObject *tuple;
-    node *tree;
-
-    static char *keywords[] = {"sequence", NULL};
-
-    if (!PyArg_ParseTupleAndKeywords(args, kw, "O:sequence2st", keywords,
-                                     &tuple))
-        return (0);
-    if (!PySequence_Check(tuple)) {
-        PyErr_SetString(PyExc_ValueError,
-                        "sequence2st() requires a single sequence argument");
-        return (0);
-    }
-    /*
-     *  Convert the tree to the internal form before checking it.
-     */
-    tree = build_node_tree(tuple);
-    if (tree != 0) {
-        int start_sym = TYPE(tree);
-        if (start_sym == eval_input) {
-            /*  Might be an eval form.  */
-            if (validate_expr_tree(tree))
-                st = parser_newstobject(tree, PyST_EXPR);
-            else
-                PyNode_Free(tree);
-        }
-        else if (start_sym == file_input) {
-            /*  This looks like an exec form so far.  */
-            if (validate_file_input(tree))
-                st = parser_newstobject(tree, PyST_SUITE);
-            else
-                PyNode_Free(tree);
-        }
-        else if (start_sym == encoding_decl) {
-            /* This looks like an encoding_decl so far. */
-            if (validate_encoding_decl(tree))
-                st = parser_newstobject(tree, PyST_SUITE);
-            else
-                PyNode_Free(tree);
-        }
-        else {
-            /*  This is a fragment, at best. */
-            PyNode_Free(tree);
-            err_string("parse tree does not use a valid start symbol");
-        }
-    }
-    /*  Make sure we throw an exception on all errors.  We should never
-     *  get this, but we'd do well to be sure something is done.
-     */
-    if (st == NULL && !PyErr_Occurred())
-        err_string("unspecified ST error occurred");
-
-    return st;
-}
-
-
-/*  node* build_node_children()
- *
- *  Iterate across the children of the current non-terminal node and build
- *  their structures.  If successful, return the root of this portion of
- *  the tree, otherwise, 0.  Any required exception will be specified already,
- *  and no memory will have been deallocated.
- *
- */
-static node*
-build_node_children(PyObject *tuple, node *root, int *line_num)
-{
-    Py_ssize_t len = PyObject_Size(tuple);
-    Py_ssize_t i;
-    int  err;
-
-    for (i = 1; i < len; ++i) {
-        /* elem must always be a sequence, however simple */
-        PyObject* elem = PySequence_GetItem(tuple, i);
-        int ok = elem != NULL;
-        long  type = 0;
-        char *strn = 0;
-
-        if (ok)
-            ok = PySequence_Check(elem);
-        if (ok) {
-            PyObject *temp = PySequence_GetItem(elem, 0);
-            if (temp == NULL)
-                ok = 0;
-            else {
-                ok = PyInt_Check(temp);
-                if (ok)
-                    type = PyInt_AS_LONG(temp);
-                Py_DECREF(temp);
-            }
-        }
-        if (!ok) {
-            PyObject *err = Py_BuildValue("os", elem,
-                                          "Illegal node construct.");
-            PyErr_SetObject(parser_error, err);
-            Py_XDECREF(err);
-            Py_XDECREF(elem);
-            return (0);
-        }
-        if (ISTERMINAL(type)) {
-            Py_ssize_t len = PyObject_Size(elem);
-            PyObject *temp;
-
-            if ((len != 2) && (len != 3)) {
-                err_string("terminal nodes must have 2 or 3 entries");
-                return 0;
-            }
-            temp = PySequence_GetItem(elem, 1);
-            if (temp == NULL)
-                return 0;
-            if (!PyString_Check(temp)) {
-                PyErr_Format(parser_error,
-                             "second item in terminal node must be a string,"
-                             " found %s",
-                             temp->ob_type->tp_name);
-                Py_DECREF(temp);
-                return 0;
-            }
-            if (len == 3) {
-                PyObject *o = PySequence_GetItem(elem, 2);
-                if (o != NULL) {
-                    if (PyInt_Check(o))
-                        *line_num = PyInt_AS_LONG(o);
-                    else {
-                        PyErr_Format(parser_error,
-                                     "third item in terminal node must be an"
-                                     " integer, found %s",
-				     temp->ob_type->tp_name);
-                        Py_DECREF(o);
-                        Py_DECREF(temp);
-                        return 0;
-                    }
-                    Py_DECREF(o);
-                }
-            }
-            len = PyString_GET_SIZE(temp) + 1;
-            strn = (char *)PyObject_MALLOC(len);
-            if (strn != NULL)
-                (void) memcpy(strn, PyString_AS_STRING(temp), len);
-            Py_DECREF(temp);
-        }
-        else if (!ISNONTERMINAL(type)) {
-            /*
-             *  It has to be one or the other; this is an error.
-             *  Throw an exception.
-             */
-            PyObject *err = Py_BuildValue("os", elem, "unknown node type.");
-            PyErr_SetObject(parser_error, err);
-            Py_XDECREF(err);
-            Py_XDECREF(elem);
-            return (0);
-        }
-        err = PyNode_AddChild(root, type, strn, *line_num, 0);
-        if (err == E_NOMEM) {
-            PyObject_FREE(strn);
-            return (node *) PyErr_NoMemory();
-        }
-        if (err == E_OVERFLOW) {
-            PyObject_FREE(strn);
-            PyErr_SetString(PyExc_ValueError,
-                            "unsupported number of child nodes");
-            return NULL;
-        }
-
-        if (ISNONTERMINAL(type)) {
-            node* new_child = CHILD(root, i - 1);
-
-            if (new_child != build_node_children(elem, new_child, line_num)) {
-                Py_XDECREF(elem);
-                return (0);
-            }
-        }
-        else if (type == NEWLINE) {     /* It's true:  we increment the     */
-            ++(*line_num);              /* line number *after* the newline! */
-        }
-        Py_XDECREF(elem);
-    }
-    return root;
-}
-
-
-static node*
-build_node_tree(PyObject *tuple)
-{
-    node* res = 0;
-    PyObject *temp = PySequence_GetItem(tuple, 0);
-    long num = -1;
-
-    if (temp != NULL)
-        num = PyInt_AsLong(temp);
-    Py_XDECREF(temp);
-    if (ISTERMINAL(num)) {
-        /*
-         *  The tuple is simple, but it doesn't start with a start symbol.
-         *  Throw an exception now and be done with it.
-         */
-        tuple = Py_BuildValue("os", tuple,
-                    "Illegal syntax-tree; cannot start with terminal symbol.");
-        PyErr_SetObject(parser_error, tuple);
-        Py_XDECREF(tuple);
-    }
-    else if (ISNONTERMINAL(num)) {
-        /*
-         *  Not efficient, but that can be handled later.
-         */
-        int line_num = 0;
-        PyObject *encoding = NULL;
-
-        if (num == encoding_decl) {
-            encoding = PySequence_GetItem(tuple, 2);
-            /* tuple isn't borrowed anymore here, need to DECREF */
-            tuple = PySequence_GetSlice(tuple, 0, 2);
-        }
-        res = PyNode_New(num);
-        if (res != NULL) {
-            if (res != build_node_children(tuple, res, &line_num)) {
-                PyNode_Free(res);
-                res = NULL;
-            }
-            if (res && encoding) {
-                Py_ssize_t len;
-                len = PyString_GET_SIZE(encoding) + 1;
-                res->n_str = (char *)PyObject_MALLOC(len);
-                if (res->n_str != NULL)
-                    (void) memcpy(res->n_str, PyString_AS_STRING(encoding), len);
-                Py_DECREF(encoding);
-                Py_DECREF(tuple);
-            }
-        }
-    }
-    else {
-        /*  The tuple is illegal -- if the number is neither TERMINAL nor
-         *  NONTERMINAL, we can't use it.  Not sure the implementation
-         *  allows this condition, but the API doesn't preclude it.
-         */
-        PyObject *err = Py_BuildValue("os", tuple,
-                                      "Illegal component tuple.");
-        PyErr_SetObject(parser_error, err);
-        Py_XDECREF(err);
-    }
-
-    return (res);
-}
-
-
-/*
- *  Validation routines used within the validation section:
- */
-static int validate_terminal(node *terminal, int type, char *string);
-
-#define validate_ampersand(ch)  validate_terminal(ch,      AMPER, "&")
-#define validate_circumflex(ch) validate_terminal(ch, CIRCUMFLEX, "^")
-#define validate_colon(ch)      validate_terminal(ch,      COLON, ":")
-#define validate_comma(ch)      validate_terminal(ch,      COMMA, ",")
-#define validate_dedent(ch)     validate_terminal(ch,     DEDENT, "")
-#define validate_equal(ch)      validate_terminal(ch,      EQUAL, "=")
-#define validate_indent(ch)     validate_terminal(ch,     INDENT, (char*)NULL)
-#define validate_lparen(ch)     validate_terminal(ch,       LPAR, "(")
-#define validate_newline(ch)    validate_terminal(ch,    NEWLINE, (char*)NULL)
-#define validate_rparen(ch)     validate_terminal(ch,       RPAR, ")")
-#define validate_semi(ch)       validate_terminal(ch,       SEMI, ";")
-#define validate_star(ch)       validate_terminal(ch,       STAR, "*")
-#define validate_vbar(ch)       validate_terminal(ch,       VBAR, "|")
-#define validate_doublestar(ch) validate_terminal(ch, DOUBLESTAR, "**")
-#define validate_dot(ch)        validate_terminal(ch,        DOT, ".")
-#define validate_at(ch)         validate_terminal(ch,         AT, "@")
-#define validate_name(ch, str)  validate_terminal(ch,       NAME, str)
-
-#define VALIDATER(n)    static int validate_##n(node *tree)
-
-VALIDATER(node);                VALIDATER(small_stmt);
-VALIDATER(class);               VALIDATER(node);
-VALIDATER(parameters);          VALIDATER(suite);
-VALIDATER(testlist);            VALIDATER(varargslist);
-VALIDATER(fpdef);               VALIDATER(fplist);
-VALIDATER(stmt);                VALIDATER(simple_stmt);
-VALIDATER(expr_stmt);           VALIDATER(power);
-VALIDATER(print_stmt);          VALIDATER(del_stmt);
-VALIDATER(return_stmt);         VALIDATER(list_iter);
-VALIDATER(raise_stmt);          VALIDATER(import_stmt);
-VALIDATER(import_name);         VALIDATER(import_from);
-VALIDATER(global_stmt);         VALIDATER(list_if);
-VALIDATER(assert_stmt);         VALIDATER(list_for);
-VALIDATER(exec_stmt);           VALIDATER(compound_stmt);
-VALIDATER(while);               VALIDATER(for);
-VALIDATER(try);                 VALIDATER(except_clause);
-VALIDATER(test);                VALIDATER(and_test);
-VALIDATER(not_test);            VALIDATER(comparison);
-VALIDATER(comp_op);             VALIDATER(expr);
-VALIDATER(xor_expr);            VALIDATER(and_expr);
-VALIDATER(shift_expr);          VALIDATER(arith_expr);
-VALIDATER(term);                VALIDATER(factor);
-VALIDATER(atom);                VALIDATER(lambdef);
-VALIDATER(trailer);             VALIDATER(subscript);
-VALIDATER(subscriptlist);       VALIDATER(sliceop);
-VALIDATER(exprlist);            VALIDATER(dictmaker);
-VALIDATER(arglist);             VALIDATER(argument);
-VALIDATER(listmaker);           VALIDATER(yield_stmt);
-VALIDATER(testlist1);           VALIDATER(gen_for);
-VALIDATER(gen_iter);            VALIDATER(gen_if);
-VALIDATER(testlist_gexp);	VALIDATER(yield_expr);
-VALIDATER(yield_or_testlist);	VALIDATER(or_test);
-VALIDATER(old_test); 		VALIDATER(old_lambdef);
-
-#undef VALIDATER
-
-#define is_even(n)      (((n) & 1) == 0)
-#define is_odd(n)       (((n) & 1) == 1)
-
-
-static int
-validate_ntype(node *n, int t)
-{
-    if (TYPE(n) != t) {
-        PyErr_Format(parser_error, "Expected node type %d, got %d.",
-                     t, TYPE(n));
-        return 0;
-    }
-    return 1;
-}
-
-
-/*  Verifies that the number of child nodes is exactly 'num', raising
- *  an exception if it isn't.  The exception message does not indicate
- *  the exact number of nodes, allowing this to be used to raise the
- *  "right" exception when the wrong number of nodes is present in a
- *  specific variant of a statement's syntax.  This is commonly used
- *  in that fashion.
- */
-static int
-validate_numnodes(node *n, int num, const char *const name)
-{
-    if (NCH(n) != num) {
-        PyErr_Format(parser_error,
-                     "Illegal number of children for %s node.", name);
-        return 0;
-    }
-    return 1;
-}
-
-
-static int
-validate_terminal(node *terminal, int type, char *string)
-{
-    int res = (validate_ntype(terminal, type)
-               && ((string == 0) || (strcmp(string, STR(terminal)) == 0)));
-
-    if (!res && !PyErr_Occurred()) {
-        PyErr_Format(parser_error,
-                     "Illegal terminal: expected \"%s\"", string);
-    }
-    return (res);
-}
-
-
-/*  X (',' X) [',']
- */
-static int
-validate_repeating_list(node *tree, int ntype, int (*vfunc)(node *),
-                        const char *const name)
-{
-    int nch = NCH(tree);
-    int res = (nch && validate_ntype(tree, ntype)
-               && vfunc(CHILD(tree, 0)));
-
-    if (!res && !PyErr_Occurred())
-        (void) validate_numnodes(tree, 1, name);
-    else {
-        if (is_even(nch))
-            res = validate_comma(CHILD(tree, --nch));
-        if (res && nch > 1) {
-            int pos = 1;
-            for ( ; res && pos < nch; pos += 2)
-                res = (validate_comma(CHILD(tree, pos))
-                       && vfunc(CHILD(tree, pos + 1)));
-        }
-    }
-    return (res);
-}
-
-
-/*  validate_class()
- *
- *  classdef:
- *      'class' NAME ['(' testlist ')'] ':' suite
- */
-static int
-validate_class(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, classdef) &&
-	       	((nch == 4) || (nch == 6) || (nch == 7)));
-
-    if (res) {
-        res = (validate_name(CHILD(tree, 0), "class")
-               && validate_ntype(CHILD(tree, 1), NAME)
-               && validate_colon(CHILD(tree, nch - 2))
-               && validate_suite(CHILD(tree, nch - 1)));
-    }
-    else {
-        (void) validate_numnodes(tree, 4, "class");
-    }
-	
-    if (res) {
-	if (nch == 7) {
-		res = ((validate_lparen(CHILD(tree, 2)) &&
-			validate_testlist(CHILD(tree, 3)) &&
-			validate_rparen(CHILD(tree, 4))));
-	}
-	else if (nch == 6) {
-		res = (validate_lparen(CHILD(tree,2)) &&
-			validate_rparen(CHILD(tree,3)));
-	}
-    }
-    return (res);
-}
-
-
-/*  if_stmt:
- *      'if' test ':' suite ('elif' test ':' suite)* ['else' ':' suite]
- */
-static int
-validate_if(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, if_stmt)
-               && (nch >= 4)
-               && validate_name(CHILD(tree, 0), "if")
-               && validate_test(CHILD(tree, 1))
-               && validate_colon(CHILD(tree, 2))
-               && validate_suite(CHILD(tree, 3)));
-
-    if (res && ((nch % 4) == 3)) {
-        /*  ... 'else' ':' suite  */
-        res = (validate_name(CHILD(tree, nch - 3), "else")
-               && validate_colon(CHILD(tree, nch - 2))
-               && validate_suite(CHILD(tree, nch - 1)));
-        nch -= 3;
-    }
-    else if (!res && !PyErr_Occurred())
-        (void) validate_numnodes(tree, 4, "if");
-    if ((nch % 4) != 0)
-        /* Will catch the case for nch < 4 */
-        res = validate_numnodes(tree, 0, "if");
-    else if (res && (nch > 4)) {
-        /*  ... ('elif' test ':' suite)+ ...  */
-        int j = 4;
-        while ((j < nch) && res) {
-            res = (validate_name(CHILD(tree, j), "elif")
-                   && validate_colon(CHILD(tree, j + 2))
-                   && validate_test(CHILD(tree, j + 1))
-                   && validate_suite(CHILD(tree, j + 3)));
-            j += 4;
-        }
-    }
-    return (res);
-}
-
-
-/*  parameters:
- *      '(' [varargslist] ')'
- *
- */
-static int
-validate_parameters(node *tree)
-{
-    int nch = NCH(tree);
-    int res = validate_ntype(tree, parameters) && ((nch == 2) || (nch == 3));
-
-    if (res) {
-        res = (validate_lparen(CHILD(tree, 0))
-               && validate_rparen(CHILD(tree, nch - 1)));
-        if (res && (nch == 3))
-            res = validate_varargslist(CHILD(tree, 1));
-    }
-    else {
-        (void) validate_numnodes(tree, 2, "parameters");
-    }
-    return (res);
-}
-
-
-/*  validate_suite()
- *
- *  suite:
- *      simple_stmt
- *    | NEWLINE INDENT stmt+ DEDENT
- */
-static int
-validate_suite(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, suite) && ((nch == 1) || (nch >= 4)));
-
-    if (res && (nch == 1))
-        res = validate_simple_stmt(CHILD(tree, 0));
-    else if (res) {
-        /*  NEWLINE INDENT stmt+ DEDENT  */
-        res = (validate_newline(CHILD(tree, 0))
-               && validate_indent(CHILD(tree, 1))
-               && validate_stmt(CHILD(tree, 2))
-               && validate_dedent(CHILD(tree, nch - 1)));
-
-        if (res && (nch > 4)) {
-            int i = 3;
-            --nch;                      /* forget the DEDENT     */
-            for ( ; res && (i < nch); ++i)
-                res = validate_stmt(CHILD(tree, i));
-        }
-        else if (nch < 4)
-            res = validate_numnodes(tree, 4, "suite");
-    }
-    return (res);
-}
-
-
-static int
-validate_testlist(node *tree)
-{
-    return (validate_repeating_list(tree, testlist,
-                                    validate_test, "testlist"));
-}
-
-
-static int
-validate_testlist1(node *tree)
-{
-    return (validate_repeating_list(tree, testlist1,
-                                    validate_test, "testlist1"));
-}
-
-
-static int
-validate_testlist_safe(node *tree)
-{
-    return (validate_repeating_list(tree, testlist_safe,
-                                    validate_old_test, "testlist_safe"));
-}
-
-
-/* '*' NAME [',' '**' NAME] | '**' NAME
- */
-static int
-validate_varargslist_trailer(node *tree, int start)
-{
-    int nch = NCH(tree);
-    int res = 0;
-    int sym;
-
-    if (nch <= start) {
-        err_string("expected variable argument trailer for varargslist");
-        return 0;
-    }
-    sym = TYPE(CHILD(tree, start));
-    if (sym == STAR) {
-        /*
-         *  ('*' NAME [',' '**' NAME]
-         */
-        if (nch-start == 2)
-            res = validate_name(CHILD(tree, start+1), NULL);
-        else if (nch-start == 5)
-            res = (validate_name(CHILD(tree, start+1), NULL)
-                   && validate_comma(CHILD(tree, start+2))
-                   && validate_doublestar(CHILD(tree, start+3))
-                   && validate_name(CHILD(tree, start+4), NULL));
-    }
-    else if (sym == DOUBLESTAR) {
-        /*
-         *  '**' NAME
-         */
-        if (nch-start == 2)
-            res = validate_name(CHILD(tree, start+1), NULL);
-    }
-    if (!res)
-        err_string("illegal variable argument trailer for varargslist");
-    return res;
-}
-
-
-/*  validate_varargslist()
- *
- *  varargslist:
- *      (fpdef ['=' test] ',')*
- *           ('*' NAME [',' '**' NAME]
- *         | '**' NAME)
- *    | fpdef ['=' test] (',' fpdef ['=' test])* [',']
- *
- */
-static int
-validate_varargslist(node *tree)
-{
-    int nch = NCH(tree);
-    int res = validate_ntype(tree, varargslist) && (nch != 0);
-    int sym;
-
-    if (!res)
-        return 0;
-    if (nch < 1) {
-        err_string("varargslist missing child nodes");
-        return 0;
-    }
-    sym = TYPE(CHILD(tree, 0));
-    if (sym == STAR || sym == DOUBLESTAR)
-        /* whole thing matches:
-         *      '*' NAME [',' '**' NAME] | '**' NAME
-         */
-        res = validate_varargslist_trailer(tree, 0);
-    else if (sym == fpdef) {
-        int i = 0;
-
-        sym = TYPE(CHILD(tree, nch-1));
-        if (sym == NAME) {
-            /*
-             *   (fpdef ['=' test] ',')+
-             *       ('*' NAME [',' '**' NAME]
-             *     | '**' NAME)
-             */
-            /* skip over (fpdef ['=' test] ',')+ */
-            while (res && (i+2 <= nch)) {
-                res = validate_fpdef(CHILD(tree, i));
-                ++i;
-                if (res && TYPE(CHILD(tree, i)) == EQUAL && (i+2 <= nch)) {
-                    res = (validate_equal(CHILD(tree, i))
-                           && validate_test(CHILD(tree, i+1)));
-                    if (res)
-                        i += 2;
-                }
-                if (res && i < nch) {
-                    res = validate_comma(CHILD(tree, i));
-                    ++i;
-                    if (res && i < nch
-                        && (TYPE(CHILD(tree, i)) == DOUBLESTAR
-                            || TYPE(CHILD(tree, i)) == STAR))
-                        break;
-                }
-            }
-            /* ... '*' NAME [',' '**' NAME] | '**' NAME
-             * i --^^^
-             */
-            if (res)
-                res = validate_varargslist_trailer(tree, i);
-        }
-        else {
-            /*
-             *  fpdef ['=' test] (',' fpdef ['=' test])* [',']
-             */
-            /* strip trailing comma node */
-            if (sym == COMMA) {
-                res = validate_comma(CHILD(tree, nch-1));
-                if (!res)
-                    return 0;
-                --nch;
-            }
-            /*
-             *  fpdef ['=' test] (',' fpdef ['=' test])*
-             */
-            res = validate_fpdef(CHILD(tree, 0));
-            ++i;
-            if (res && (i+2 <= nch) && TYPE(CHILD(tree, i)) == EQUAL) {
-                res = (validate_equal(CHILD(tree, i))
-                       && validate_test(CHILD(tree, i+1)));
-                i += 2;
-            }
-            /*
-             *  ... (',' fpdef ['=' test])*
-             *  i ---^^^
-             */
-            while (res && (nch - i) >= 2) {
-                res = (validate_comma(CHILD(tree, i))
-                       && validate_fpdef(CHILD(tree, i+1)));
-                i += 2;
-                if (res && (nch - i) >= 2 && TYPE(CHILD(tree, i)) == EQUAL) {
-                    res = (validate_equal(CHILD(tree, i))
-                           && validate_test(CHILD(tree, i+1)));
-                    i += 2;
-                }
-            }
-            if (res && nch - i != 0) {
-                res = 0;
-                err_string("illegal formation for varargslist");
-            }
-        }
-    }
-    return res;
-}
-
-
-/*  list_iter:  list_for | list_if
- */
-static int
-validate_list_iter(node *tree)
-{
-    int res = (validate_ntype(tree, list_iter)
-               && validate_numnodes(tree, 1, "list_iter"));
-    if (res && TYPE(CHILD(tree, 0)) == list_for)
-        res = validate_list_for(CHILD(tree, 0));
-    else
-        res = validate_list_if(CHILD(tree, 0));
-
-    return res;
-}
-
-/*  gen_iter:  gen_for | gen_if
- */
-static int
-validate_gen_iter(node *tree)
-{
-    int res = (validate_ntype(tree, gen_iter)
-               && validate_numnodes(tree, 1, "gen_iter"));
-    if (res && TYPE(CHILD(tree, 0)) == gen_for)
-        res = validate_gen_for(CHILD(tree, 0));
-    else
-        res = validate_gen_if(CHILD(tree, 0));
-
-    return res;
-}
-
-/*  list_for:  'for' exprlist 'in' testlist [list_iter]
- */
-static int
-validate_list_for(node *tree)
-{
-    int nch = NCH(tree);
-    int res;
-
-    if (nch == 5)
-        res = validate_list_iter(CHILD(tree, 4));
-    else
-        res = validate_numnodes(tree, 4, "list_for");
-
-    if (res)
-        res = (validate_name(CHILD(tree, 0), "for")
-               && validate_exprlist(CHILD(tree, 1))
-               && validate_name(CHILD(tree, 2), "in")
-               && validate_testlist_safe(CHILD(tree, 3)));
-
-    return res;
-}
-
-/*  gen_for:  'for' exprlist 'in' test [gen_iter]
- */
-static int
-validate_gen_for(node *tree)
-{
-    int nch = NCH(tree);
-    int res;
-
-    if (nch == 5)
-        res = validate_gen_iter(CHILD(tree, 4));
-    else
-        res = validate_numnodes(tree, 4, "gen_for");
-
-    if (res)
-        res = (validate_name(CHILD(tree, 0), "for")
-               && validate_exprlist(CHILD(tree, 1))
-               && validate_name(CHILD(tree, 2), "in")
-               && validate_or_test(CHILD(tree, 3)));
-
-    return res;
-}
-
-/*  list_if:  'if' old_test [list_iter]
- */
-static int
-validate_list_if(node *tree)
-{
-    int nch = NCH(tree);
-    int res;
-
-    if (nch == 3)
-        res = validate_list_iter(CHILD(tree, 2));
-    else
-        res = validate_numnodes(tree, 2, "list_if");
-
-    if (res)
-        res = (validate_name(CHILD(tree, 0), "if")
-               && validate_old_test(CHILD(tree, 1)));
-
-    return res;
-}
-
-/*  gen_if:  'if' old_test [gen_iter]
- */
-static int
-validate_gen_if(node *tree)
-{
-    int nch = NCH(tree);
-    int res;
-
-    if (nch == 3)
-        res = validate_gen_iter(CHILD(tree, 2));
-    else
-        res = validate_numnodes(tree, 2, "gen_if");
-    
-    if (res)
-        res = (validate_name(CHILD(tree, 0), "if")
-               && validate_old_test(CHILD(tree, 1)));
-
-    return res;
-}
-
-/*  validate_fpdef()
- *
- *  fpdef:
- *      NAME
- *    | '(' fplist ')'
- */
-static int
-validate_fpdef(node *tree)
-{
-    int nch = NCH(tree);
-    int res = validate_ntype(tree, fpdef);
-
-    if (res) {
-        if (nch == 1)
-            res = validate_ntype(CHILD(tree, 0), NAME);
-        else if (nch == 3)
-            res = (validate_lparen(CHILD(tree, 0))
-                   && validate_fplist(CHILD(tree, 1))
-                   && validate_rparen(CHILD(tree, 2)));
-        else
-            res = validate_numnodes(tree, 1, "fpdef");
-    }
-    return (res);
-}
-
-
-static int
-validate_fplist(node *tree)
-{
-    return (validate_repeating_list(tree, fplist,
-                                    validate_fpdef, "fplist"));
-}
-
-
-/*  simple_stmt | compound_stmt
- *
- */
-static int
-validate_stmt(node *tree)
-{
-    int res = (validate_ntype(tree, stmt)
-               && validate_numnodes(tree, 1, "stmt"));
-
-    if (res) {
-        tree = CHILD(tree, 0);
-
-        if (TYPE(tree) == simple_stmt)
-            res = validate_simple_stmt(tree);
-        else
-            res = validate_compound_stmt(tree);
-    }
-    return (res);
-}
-
-
-/*  small_stmt (';' small_stmt)* [';'] NEWLINE
- *
- */
-static int
-validate_simple_stmt(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, simple_stmt)
-               && (nch >= 2)
-               && validate_small_stmt(CHILD(tree, 0))
-               && validate_newline(CHILD(tree, nch - 1)));
-
-    if (nch < 2)
-        res = validate_numnodes(tree, 2, "simple_stmt");
-    --nch;                              /* forget the NEWLINE    */
-    if (res && is_even(nch))
-        res = validate_semi(CHILD(tree, --nch));
-    if (res && (nch > 2)) {
-        int i;
-
-        for (i = 1; res && (i < nch); i += 2)
-            res = (validate_semi(CHILD(tree, i))
-                   && validate_small_stmt(CHILD(tree, i + 1)));
-    }
-    return (res);
-}
-
-
-static int
-validate_small_stmt(node *tree)
-{
-    int nch = NCH(tree);
-    int res = validate_numnodes(tree, 1, "small_stmt");
-
-    if (res) {
-        int ntype = TYPE(CHILD(tree, 0));
-
-        if (  (ntype == expr_stmt)
-              || (ntype == print_stmt)
-              || (ntype == del_stmt)
-              || (ntype == pass_stmt)
-              || (ntype == flow_stmt)
-              || (ntype == import_stmt)
-              || (ntype == global_stmt)
-              || (ntype == assert_stmt)
-              || (ntype == exec_stmt))
-            res = validate_node(CHILD(tree, 0));
-        else {
-            res = 0;
-            err_string("illegal small_stmt child type");
-        }
-    }
-    else if (nch == 1) {
-        res = 0;
-        PyErr_Format(parser_error,
-                     "Unrecognized child node of small_stmt: %d.",
-                     TYPE(CHILD(tree, 0)));
-    }
-    return (res);
-}
-
-
-/*  compound_stmt:
- *      if_stmt | while_stmt | for_stmt | try_stmt | funcdef | classdef
- */
-static int
-validate_compound_stmt(node *tree)
-{
-    int res = (validate_ntype(tree, compound_stmt)
-               && validate_numnodes(tree, 1, "compound_stmt"));
-    int ntype;
-
-    if (!res)
-        return (0);
-
-    tree = CHILD(tree, 0);
-    ntype = TYPE(tree);
-    if (  (ntype == if_stmt)
-          || (ntype == while_stmt)
-          || (ntype == for_stmt)
-          || (ntype == try_stmt)
-          || (ntype == funcdef)
-          || (ntype == classdef))
-        res = validate_node(tree);
-    else {
-        res = 0;
-        PyErr_Format(parser_error,
-                     "Illegal compound statement type: %d.", TYPE(tree));
-    }
-    return (res);
-}
-
-
-static int
-validate_yield_or_testlist(node *tree)
-{
-	if (TYPE(tree) == yield_expr) 
-		return validate_yield_expr(tree);
-	else
-		return validate_testlist(tree);
-}
-
-static int
-validate_expr_stmt(node *tree)
-{
-    int j;
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, expr_stmt)
-               && is_odd(nch)
-               && validate_testlist(CHILD(tree, 0)));
-
-    if (res && nch == 3
-        && TYPE(CHILD(tree, 1)) == augassign) {
-        res = validate_numnodes(CHILD(tree, 1), 1, "augassign")
-		&& validate_yield_or_testlist(CHILD(tree, 2));
-
-        if (res) {
-            char *s = STR(CHILD(CHILD(tree, 1), 0));
-
-            res = (strcmp(s, "+=") == 0
-                   || strcmp(s, "-=") == 0
-                   || strcmp(s, "*=") == 0
-                   || strcmp(s, "/=") == 0
-                   || strcmp(s, "//=") == 0
-                   || strcmp(s, "%=") == 0
-                   || strcmp(s, "&=") == 0
-                   || strcmp(s, "|=") == 0
-                   || strcmp(s, "^=") == 0
-                   || strcmp(s, "<<=") == 0
-                   || strcmp(s, ">>=") == 0
-                   || strcmp(s, "**=") == 0);
-            if (!res)
-                err_string("illegal augmmented assignment operator");
-        }
-    }
-    else {
-        for (j = 1; res && (j < nch); j += 2)
-            res = validate_equal(CHILD(tree, j))
-                   && validate_yield_or_testlist(CHILD(tree, j + 1));
-    }
-    return (res);
-}
-
-
-/*  print_stmt:
- *
- *      'print' ( [ test (',' test)* [','] ]
- *              | '>>' test [ (',' test)+ [','] ] )
- */
-static int
-validate_print_stmt(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, print_stmt)
-               && (nch > 0)
-               && validate_name(CHILD(tree, 0), "print"));
-
-    if (res && nch > 1) {
-        int sym = TYPE(CHILD(tree, 1));
-        int i = 1;
-        int allow_trailing_comma = 1;
-
-        if (sym == test)
-            res = validate_test(CHILD(tree, i++));
-        else {
-            if (nch < 3)
-                res = validate_numnodes(tree, 3, "print_stmt");
-            else {
-                res = (validate_ntype(CHILD(tree, i), RIGHTSHIFT)
-                       && validate_test(CHILD(tree, i+1)));
-                i += 2;
-                allow_trailing_comma = 0;
-            }
-        }
-        if (res) {
-            /*  ... (',' test)* [',']  */
-            while (res && i+2 <= nch) {
-                res = (validate_comma(CHILD(tree, i))
-                       && validate_test(CHILD(tree, i+1)));
-                allow_trailing_comma = 1;
-                i += 2;
-            }
-            if (res && !allow_trailing_comma)
-                res = validate_numnodes(tree, i, "print_stmt");
-            else if (res && i < nch)
-                res = validate_comma(CHILD(tree, i));
-        }
-    }
-    return (res);
-}
-
-
-static int
-validate_del_stmt(node *tree)
-{
-    return (validate_numnodes(tree, 2, "del_stmt")
-            && validate_name(CHILD(tree, 0), "del")
-            && validate_exprlist(CHILD(tree, 1)));
-}
-
-
-static int
-validate_return_stmt(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, return_stmt)
-               && ((nch == 1) || (nch == 2))
-               && validate_name(CHILD(tree, 0), "return"));
-
-    if (res && (nch == 2))
-        res = validate_testlist(CHILD(tree, 1));
-
-    return (res);
-}
-
-
-static int
-validate_raise_stmt(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, raise_stmt)
-               && ((nch == 1) || (nch == 2) || (nch == 4) || (nch == 6)));
-
-    if (res) {
-        res = validate_name(CHILD(tree, 0), "raise");
-        if (res && (nch >= 2))
-            res = validate_test(CHILD(tree, 1));
-        if (res && nch > 2) {
-            res = (validate_comma(CHILD(tree, 2))
-                   && validate_test(CHILD(tree, 3)));
-            if (res && (nch > 4))
-                res = (validate_comma(CHILD(tree, 4))
-                       && validate_test(CHILD(tree, 5)));
-        }
-    }
-    else
-        (void) validate_numnodes(tree, 2, "raise");
-    if (res && (nch == 4))
-        res = (validate_comma(CHILD(tree, 2))
-               && validate_test(CHILD(tree, 3)));
-
-    return (res);
-}
-
-
-/* yield_expr: 'yield' [testlist]
- */
-static int
-validate_yield_expr(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, yield_expr)
-               && ((nch == 1) || (nch == 2))
-               && validate_name(CHILD(tree, 0), "yield"));
-
-    if (res && (nch == 2))
-        res = validate_testlist(CHILD(tree, 1));
-
-    return (res);
-}
-
-
-/* yield_stmt: yield_expr
- */
-static int
-validate_yield_stmt(node *tree)
-{
-    return (validate_ntype(tree, yield_stmt)
-            && validate_numnodes(tree, 1, "yield_stmt")
-            && validate_yield_expr(CHILD(tree, 0)));
-}
-
-
-static int
-validate_import_as_name(node *tree)
-{
-    int nch = NCH(tree);
-    int ok = validate_ntype(tree, import_as_name);
-
-    if (ok) {
-        if (nch == 1)
-            ok = validate_name(CHILD(tree, 0), NULL);
-        else if (nch == 3)
-            ok = (validate_name(CHILD(tree, 0), NULL)
-                  && validate_name(CHILD(tree, 1), "as")
-                  && validate_name(CHILD(tree, 2), NULL));
-        else
-            ok = validate_numnodes(tree, 3, "import_as_name");
-    }
-    return ok;
-}
-
-
-/* dotted_name:  NAME ("." NAME)*
- */
-static int
-validate_dotted_name(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, dotted_name)
-               && is_odd(nch)
-               && validate_name(CHILD(tree, 0), NULL));
-    int i;
-
-    for (i = 1; res && (i < nch); i += 2) {
-        res = (validate_dot(CHILD(tree, i))
-               && validate_name(CHILD(tree, i+1), NULL));
-    }
-    return res;
-}
-
-
-/* dotted_as_name:  dotted_name [NAME NAME]
- */
-static int
-validate_dotted_as_name(node *tree)
-{
-    int nch = NCH(tree);
-    int res = validate_ntype(tree, dotted_as_name);
-
-    if (res) {
-        if (nch == 1)
-            res = validate_dotted_name(CHILD(tree, 0));
-        else if (nch == 3)
-            res = (validate_dotted_name(CHILD(tree, 0))
-                   && validate_name(CHILD(tree, 1), "as")
-                   && validate_name(CHILD(tree, 2), NULL));
-        else {
-            res = 0;
-            err_string("illegal number of children for dotted_as_name");
-        }
-    }
-    return res;
-}
-
-
-/* dotted_as_name (',' dotted_as_name)* */
-static int
-validate_dotted_as_names(node *tree)
-{
-	int nch = NCH(tree);
-	int res = is_odd(nch) && validate_dotted_as_name(CHILD(tree, 0));
-	int i;
-
-	for (i = 1; res && (i < nch); i += 2)
-	    res = (validate_comma(CHILD(tree, i))
-		   && validate_dotted_as_name(CHILD(tree, i + 1)));
-	return (res);
-}
-
-
-/* import_as_name (',' import_as_name)* [','] */
-static int
-validate_import_as_names(node *tree)
-{
-    int nch = NCH(tree);
-    int res = validate_import_as_name(CHILD(tree, 0));
-    int i;
-
-    for (i = 1; res && (i + 1 < nch); i += 2)
-	res = (validate_comma(CHILD(tree, i))
-	       && validate_import_as_name(CHILD(tree, i + 1)));
-    return (res);
-}
-
-
-/* 'import' dotted_as_names */
-static int
-validate_import_name(node *tree)
-{
-	return (validate_ntype(tree, import_name)
-		&& validate_numnodes(tree, 2, "import_name")
-		&& validate_name(CHILD(tree, 0), "import")
-		&& validate_dotted_as_names(CHILD(tree, 1)));
-}
-
-/* Helper function to count the number of leading dots in 
- * 'from ...module import name'
- */
-static int
-count_from_dots(node *tree)
-{
-        int i;
-        for (i = 0; i < NCH(tree); i++)
-		if (TYPE(CHILD(tree, i)) != DOT)
-			break;
-        return i;
-}
-
-/* 'from' ('.'* dotted_name | '.') 'import' ('*' | '(' import_as_names ')' |
- *     import_as_names
- */
-static int
-validate_import_from(node *tree)
-{
-	int nch = NCH(tree);
-	int ndots = count_from_dots(tree);
-	int havename = (TYPE(CHILD(tree, ndots + 1)) == dotted_name);
-	int offset = ndots + havename;
-	int res = validate_ntype(tree, import_from)
-		&& (nch >= 4 + ndots)
-		&& validate_name(CHILD(tree, 0), "from")
-		&& (!havename || validate_dotted_name(CHILD(tree, ndots + 1)))
-		&& validate_name(CHILD(tree, offset + 1), "import");
-
-	if (res && TYPE(CHILD(tree, offset + 2)) == LPAR)
-	    res = ((nch == offset + 5)
-		   && validate_lparen(CHILD(tree, offset + 2))
-		   && validate_import_as_names(CHILD(tree, offset + 3))
-		   && validate_rparen(CHILD(tree, offset + 4)));
-	else if (res && TYPE(CHILD(tree, offset + 2)) != STAR)
-	    res = validate_import_as_names(CHILD(tree, offset + 2));
-	return (res);
-}
-
-
-/* import_stmt: import_name | import_from */
-static int
-validate_import_stmt(node *tree)
-{
-    int nch = NCH(tree);
-    int res = validate_numnodes(tree, 1, "import_stmt");
-
-    if (res) {
-	int ntype = TYPE(CHILD(tree, 0));
-
-	if (ntype == import_name || ntype == import_from)
-            res = validate_node(CHILD(tree, 0));
-        else {
-            res = 0;
-            err_string("illegal import_stmt child type");
-        }
-    }
-    else if (nch == 1) {
-        res = 0;
-        PyErr_Format(parser_error,
-                     "Unrecognized child node of import_stmt: %d.",
-                     TYPE(CHILD(tree, 0)));
-    }
-    return (res);
-}
-
-
-
-
-static int
-validate_global_stmt(node *tree)
-{
-    int j;
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, global_stmt)
-               && is_even(nch) && (nch >= 2));
-
-    if (!res && !PyErr_Occurred())
-        err_string("illegal global statement");
-
-    if (res)
-        res = (validate_name(CHILD(tree, 0), "global")
-               && validate_ntype(CHILD(tree, 1), NAME));
-    for (j = 2; res && (j < nch); j += 2)
-        res = (validate_comma(CHILD(tree, j))
-               && validate_ntype(CHILD(tree, j + 1), NAME));
-
-    return (res);
-}
-
-
-/*  exec_stmt:
- *
- *  'exec' expr ['in' test [',' test]]
- */
-static int
-validate_exec_stmt(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, exec_stmt)
-               && ((nch == 2) || (nch == 4) || (nch == 6))
-               && validate_name(CHILD(tree, 0), "exec")
-               && validate_expr(CHILD(tree, 1)));
-
-    if (!res && !PyErr_Occurred())
-        err_string("illegal exec statement");
-    if (res && (nch > 2))
-        res = (validate_name(CHILD(tree, 2), "in")
-               && validate_test(CHILD(tree, 3)));
-    if (res && (nch == 6))
-        res = (validate_comma(CHILD(tree, 4))
-               && validate_test(CHILD(tree, 5)));
-
-    return (res);
-}
-
-
-/*  assert_stmt:
- *
- *  'assert' test [',' test]
- */
-static int
-validate_assert_stmt(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, assert_stmt)
-               && ((nch == 2) || (nch == 4))
-               && (validate_name(CHILD(tree, 0), "assert"))
-               && validate_test(CHILD(tree, 1)));
-
-    if (!res && !PyErr_Occurred())
-        err_string("illegal assert statement");
-    if (res && (nch > 2))
-        res = (validate_comma(CHILD(tree, 2))
-               && validate_test(CHILD(tree, 3)));
-
-    return (res);
-}
-
-
-static int
-validate_while(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, while_stmt)
-               && ((nch == 4) || (nch == 7))
-               && validate_name(CHILD(tree, 0), "while")
-               && validate_test(CHILD(tree, 1))
-               && validate_colon(CHILD(tree, 2))
-               && validate_suite(CHILD(tree, 3)));
-
-    if (res && (nch == 7))
-        res = (validate_name(CHILD(tree, 4), "else")
-               && validate_colon(CHILD(tree, 5))
-               && validate_suite(CHILD(tree, 6)));
-
-    return (res);
-}
-
-
-static int
-validate_for(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, for_stmt)
-               && ((nch == 6) || (nch == 9))
-               && validate_name(CHILD(tree, 0), "for")
-               && validate_exprlist(CHILD(tree, 1))
-               && validate_name(CHILD(tree, 2), "in")
-               && validate_testlist(CHILD(tree, 3))
-               && validate_colon(CHILD(tree, 4))
-               && validate_suite(CHILD(tree, 5)));
-
-    if (res && (nch == 9))
-        res = (validate_name(CHILD(tree, 6), "else")
-               && validate_colon(CHILD(tree, 7))
-               && validate_suite(CHILD(tree, 8)));
-
-    return (res);
-}
-
-
-/*  try_stmt:
- *      'try' ':' suite (except_clause ':' suite)+ ['else' ':' suite]
- *    | 'try' ':' suite 'finally' ':' suite
- *
- */
-static int
-validate_try(node *tree)
-{
-    int nch = NCH(tree);
-    int pos = 3;
-    int res = (validate_ntype(tree, try_stmt)
-               && (nch >= 6) && ((nch % 3) == 0));
-
-    if (res)
-        res = (validate_name(CHILD(tree, 0), "try")
-               && validate_colon(CHILD(tree, 1))
-               && validate_suite(CHILD(tree, 2))
-               && validate_colon(CHILD(tree, nch - 2))
-               && validate_suite(CHILD(tree, nch - 1)));
-    else if (!PyErr_Occurred()) {
-        const char* name = "except";
-        if (TYPE(CHILD(tree, nch - 3)) != except_clause)
-            name = STR(CHILD(tree, nch - 3));
-
-        PyErr_Format(parser_error,
-                     "Illegal number of children for try/%s node.", name);
-    }
-    /*  Skip past except_clause sections:  */
-    while (res && (TYPE(CHILD(tree, pos)) == except_clause)) {
-        res = (validate_except_clause(CHILD(tree, pos))
-               && validate_colon(CHILD(tree, pos + 1))
-               && validate_suite(CHILD(tree, pos + 2)));
-        pos += 3;
-    }
-    if (res && (pos < nch)) {
-        res = validate_ntype(CHILD(tree, pos), NAME);
-        if (res && (strcmp(STR(CHILD(tree, pos)), "finally") == 0))
-            res = (validate_numnodes(tree, 6, "try/finally")
-                   && validate_colon(CHILD(tree, 4))
-                   && validate_suite(CHILD(tree, 5)));
-        else if (res) {
-            if (nch == (pos + 3)) {
-                res = ((strcmp(STR(CHILD(tree, pos)), "except") == 0)
-                       || (strcmp(STR(CHILD(tree, pos)), "else") == 0));
-                if (!res)
-                    err_string("illegal trailing triple in try statement");
-            }
-            else if (nch == (pos + 6)) {
-                res = (validate_name(CHILD(tree, pos), "except")
-                       && validate_colon(CHILD(tree, pos + 1))
-                       && validate_suite(CHILD(tree, pos + 2))
-                       && validate_name(CHILD(tree, pos + 3), "else"));
-            }
-            else
-                res = validate_numnodes(tree, pos + 3, "try/except");
-        }
-    }
-    return (res);
-}
-
-
-static int
-validate_except_clause(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, except_clause)
-               && ((nch == 1) || (nch == 2) || (nch == 4))
-               && validate_name(CHILD(tree, 0), "except"));
-
-    if (res && (nch > 1))
-        res = validate_test(CHILD(tree, 1));
-    if (res && (nch == 4))
-        res = (validate_comma(CHILD(tree, 2))
-               && validate_test(CHILD(tree, 3)));
-
-    return (res);
-}
-
-
-static int
-validate_test(node *tree)
-{
-    int nch = NCH(tree);
-    int res = validate_ntype(tree, test) && is_odd(nch);
-
-    if (res && (TYPE(CHILD(tree, 0)) == lambdef))
-        res = ((nch == 1)
-               && validate_lambdef(CHILD(tree, 0)));
-    else if (res) {
-        res = validate_or_test(CHILD(tree, 0));
-        res = (res && (nch == 1 || (nch == 5 &&
-            validate_name(CHILD(tree, 1), "if") &&
-            validate_or_test(CHILD(tree, 2)) &&
-            validate_name(CHILD(tree, 3), "else") &&
-            validate_test(CHILD(tree, 4)))));
-    }
-    return (res);
-}
-
-static int
-validate_old_test(node *tree)
-{
-    int nch = NCH(tree);
-    int res = validate_ntype(tree, old_test) && (nch == 1);
-
-    if (res && (TYPE(CHILD(tree, 0)) == old_lambdef))
-        res = (validate_old_lambdef(CHILD(tree, 0)));
-    else if (res) {
-        res = (validate_or_test(CHILD(tree, 0)));
-    }
-    return (res);
-}
-
-static int
-validate_or_test(node *tree)
-{
-    int nch = NCH(tree);
-    int res = validate_ntype(tree, or_test) && is_odd(nch);
-
-    if (res) {
-        int pos;
-        res = validate_and_test(CHILD(tree, 0));
-        for (pos = 1; res && (pos < nch); pos += 2)
-            res = (validate_name(CHILD(tree, pos), "or")
-                   && validate_and_test(CHILD(tree, pos + 1)));
-    }
-    return (res);
-}
-
-
-static int
-validate_and_test(node *tree)
-{
-    int pos;
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, and_test)
-               && is_odd(nch)
-               && validate_not_test(CHILD(tree, 0)));
-
-    for (pos = 1; res && (pos < nch); pos += 2)
-        res = (validate_name(CHILD(tree, pos), "and")
-               && validate_not_test(CHILD(tree, 0)));
-
-    return (res);
-}
-
-
-static int
-validate_not_test(node *tree)
-{
-    int nch = NCH(tree);
-    int res = validate_ntype(tree, not_test) && ((nch == 1) || (nch == 2));
-
-    if (res) {
-        if (nch == 2)
-            res = (validate_name(CHILD(tree, 0), "not")
-                   && validate_not_test(CHILD(tree, 1)));
-        else if (nch == 1)
-            res = validate_comparison(CHILD(tree, 0));
-    }
-    return (res);
-}
-
-
-static int
-validate_comparison(node *tree)
-{
-    int pos;
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, comparison)
-               && is_odd(nch)
-               && validate_expr(CHILD(tree, 0)));
-
-    for (pos = 1; res && (pos < nch); pos += 2)
-        res = (validate_comp_op(CHILD(tree, pos))
-               && validate_expr(CHILD(tree, pos + 1)));
-
-    return (res);
-}
-
-
-static int
-validate_comp_op(node *tree)
-{
-    int res = 0;
-    int nch = NCH(tree);
-
-    if (!validate_ntype(tree, comp_op))
-        return (0);
-    if (nch == 1) {
-        /*
-         *  Only child will be a terminal with a well-defined symbolic name
-         *  or a NAME with a string of either 'is' or 'in'
-         */
-        tree = CHILD(tree, 0);
-        switch (TYPE(tree)) {
-            case LESS:
-            case GREATER:
-            case EQEQUAL:
-            case EQUAL:
-            case LESSEQUAL:
-            case GREATEREQUAL:
-            case NOTEQUAL:
-              res = 1;
-              break;
-            case NAME:
-              res = ((strcmp(STR(tree), "in") == 0)
-                     || (strcmp(STR(tree), "is") == 0));
-              if (!res) {
-                  PyErr_Format(parser_error,
-                               "illegal operator '%s'", STR(tree));
-              }
-              break;
-          default:
-              err_string("illegal comparison operator type");
-              break;
-        }
-    }
-    else if ((res = validate_numnodes(tree, 2, "comp_op")) != 0) {
-        res = (validate_ntype(CHILD(tree, 0), NAME)
-               && validate_ntype(CHILD(tree, 1), NAME)
-               && (((strcmp(STR(CHILD(tree, 0)), "is") == 0)
-                    && (strcmp(STR(CHILD(tree, 1)), "not") == 0))
-                   || ((strcmp(STR(CHILD(tree, 0)), "not") == 0)
-                       && (strcmp(STR(CHILD(tree, 1)), "in") == 0))));
-        if (!res && !PyErr_Occurred())
-            err_string("unknown comparison operator");
-    }
-    return (res);
-}
-
-
-static int
-validate_expr(node *tree)
-{
-    int j;
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, expr)
-               && is_odd(nch)
-               && validate_xor_expr(CHILD(tree, 0)));
-
-    for (j = 2; res && (j < nch); j += 2)
-        res = (validate_xor_expr(CHILD(tree, j))
-               && validate_vbar(CHILD(tree, j - 1)));
-
-    return (res);
-}
-
-
-static int
-validate_xor_expr(node *tree)
-{
-    int j;
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, xor_expr)
-               && is_odd(nch)
-               && validate_and_expr(CHILD(tree, 0)));
-
-    for (j = 2; res && (j < nch); j += 2)
-        res = (validate_circumflex(CHILD(tree, j - 1))
-               && validate_and_expr(CHILD(tree, j)));
-
-    return (res);
-}
-
-
-static int
-validate_and_expr(node *tree)
-{
-    int pos;
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, and_expr)
-               && is_odd(nch)
-               && validate_shift_expr(CHILD(tree, 0)));
-
-    for (pos = 1; res && (pos < nch); pos += 2)
-        res = (validate_ampersand(CHILD(tree, pos))
-               && validate_shift_expr(CHILD(tree, pos + 1)));
-
-    return (res);
-}
-
-
-static int
-validate_chain_two_ops(node *tree, int (*termvalid)(node *), int op1, int op2)
- {
-    int pos = 1;
-    int nch = NCH(tree);
-    int res = (is_odd(nch)
-               && (*termvalid)(CHILD(tree, 0)));
-
-    for ( ; res && (pos < nch); pos += 2) {
-        if (TYPE(CHILD(tree, pos)) != op1)
-            res = validate_ntype(CHILD(tree, pos), op2);
-        if (res)
-            res = (*termvalid)(CHILD(tree, pos + 1));
-    }
-    return (res);
-}
-
-
-static int
-validate_shift_expr(node *tree)
-{
-    return (validate_ntype(tree, shift_expr)
-            && validate_chain_two_ops(tree, validate_arith_expr,
-                                      LEFTSHIFT, RIGHTSHIFT));
-}
-
-
-static int
-validate_arith_expr(node *tree)
-{
-    return (validate_ntype(tree, arith_expr)
-            && validate_chain_two_ops(tree, validate_term, PLUS, MINUS));
-}
-
-
-static int
-validate_term(node *tree)
-{
-    int pos = 1;
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, term)
-               && is_odd(nch)
-               && validate_factor(CHILD(tree, 0)));
-
-    for ( ; res && (pos < nch); pos += 2)
-        res = (((TYPE(CHILD(tree, pos)) == STAR)
-               || (TYPE(CHILD(tree, pos)) == SLASH)
-               || (TYPE(CHILD(tree, pos)) == DOUBLESLASH)
-               || (TYPE(CHILD(tree, pos)) == PERCENT))
-               && validate_factor(CHILD(tree, pos + 1)));
-
-    return (res);
-}
-
-
-/*  factor:
- *
- *  factor: ('+'|'-'|'~') factor | power
- */
-static int
-validate_factor(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, factor)
-               && (((nch == 2)
-                    && ((TYPE(CHILD(tree, 0)) == PLUS)
-                        || (TYPE(CHILD(tree, 0)) == MINUS)
-                        || (TYPE(CHILD(tree, 0)) == TILDE))
-                    && validate_factor(CHILD(tree, 1)))
-                   || ((nch == 1)
-                       && validate_power(CHILD(tree, 0)))));
-    return (res);
-}
-
-
-/*  power:
- *
- *  power: atom trailer* ('**' factor)*
- */
-static int
-validate_power(node *tree)
-{
-    int pos = 1;
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, power) && (nch >= 1)
-               && validate_atom(CHILD(tree, 0)));
-
-    while (res && (pos < nch) && (TYPE(CHILD(tree, pos)) == trailer))
-        res = validate_trailer(CHILD(tree, pos++));
-    if (res && (pos < nch)) {
-        if (!is_even(nch - pos)) {
-            err_string("illegal number of nodes for 'power'");
-            return (0);
-        }
-        for ( ; res && (pos < (nch - 1)); pos += 2)
-            res = (validate_doublestar(CHILD(tree, pos))
-                   && validate_factor(CHILD(tree, pos + 1)));
-    }
-    return (res);
-}
-
-
-static int
-validate_atom(node *tree)
-{
-    int pos;
-    int nch = NCH(tree);
-    int res = validate_ntype(tree, atom);
-
-    if (res && nch < 1)
-        res = validate_numnodes(tree, nch+1, "atom");
-    if (res) {
-        switch (TYPE(CHILD(tree, 0))) {
-          case LPAR:
-            res = ((nch <= 3)
-                   && (validate_rparen(CHILD(tree, nch - 1))));
-
-            if (res && (nch == 3)) {
-		if (TYPE(CHILD(tree, 1))==yield_expr)
-			res = validate_yield_expr(CHILD(tree, 1));
-		else
-                	res = validate_testlist_gexp(CHILD(tree, 1));
-	    }
-            break;
-          case LSQB:
-            if (nch == 2)
-                res = validate_ntype(CHILD(tree, 1), RSQB);
-            else if (nch == 3)
-                res = (validate_listmaker(CHILD(tree, 1))
-                       && validate_ntype(CHILD(tree, 2), RSQB));
-            else {
-                res = 0;
-                err_string("illegal list display atom");
-            }
-            break;
-          case LBRACE:
-            res = ((nch <= 3)
-                   && validate_ntype(CHILD(tree, nch - 1), RBRACE));
-
-            if (res && (nch == 3))
-                res = validate_dictmaker(CHILD(tree, 1));
-            break;
-          case BACKQUOTE:
-            res = ((nch == 3)
-                   && validate_testlist1(CHILD(tree, 1))
-                   && validate_ntype(CHILD(tree, 2), BACKQUOTE));
-            break;
-          case NAME:
-          case NUMBER:
-            res = (nch == 1);
-            break;
-          case STRING:
-            for (pos = 1; res && (pos < nch); ++pos)
-                res = validate_ntype(CHILD(tree, pos), STRING);
-            break;
-          default:
-            res = 0;
-            break;
-        }
-    }
-    return (res);
-}
-
-
-/*  listmaker:
- *    test ( list_for | (',' test)* [','] )
- */
-static int
-validate_listmaker(node *tree)
-{
-    int nch = NCH(tree);
-    int ok = nch;
-
-    if (nch == 0)
-        err_string("missing child nodes of listmaker");
-    else
-        ok = validate_test(CHILD(tree, 0));
-
-    /*
-     *  list_for | (',' test)* [',']
-     */
-    if (nch == 2 && TYPE(CHILD(tree, 1)) == list_for)
-        ok = validate_list_for(CHILD(tree, 1));
-    else {
-        /*  (',' test)* [',']  */
-        int i = 1;
-        while (ok && nch - i >= 2) {
-            ok = (validate_comma(CHILD(tree, i))
-                  && validate_test(CHILD(tree, i+1)));
-            i += 2;
-        }
-        if (ok && i == nch-1)
-            ok = validate_comma(CHILD(tree, i));
-        else if (i != nch) {
-            ok = 0;
-            err_string("illegal trailing nodes for listmaker");
-        }
-    }
-    return ok;
-}
-
-/*  testlist_gexp:
- *    test ( gen_for | (',' test)* [','] )
- */
-static int
-validate_testlist_gexp(node *tree)
-{
-    int nch = NCH(tree);
-    int ok = nch;
-
-    if (nch == 0)
-        err_string("missing child nodes of testlist_gexp");
-    else {
-        ok = validate_test(CHILD(tree, 0));
-    }
-
-    /*
-     *  gen_for | (',' test)* [',']
-     */
-    if (nch == 2 && TYPE(CHILD(tree, 1)) == gen_for)
-        ok = validate_gen_for(CHILD(tree, 1));
-    else {
-        /*  (',' test)* [',']  */
-        int i = 1;
-        while (ok && nch - i >= 2) {
-            ok = (validate_comma(CHILD(tree, i))
-                  && validate_test(CHILD(tree, i+1)));
-            i += 2;
-        }
-        if (ok && i == nch-1)
-            ok = validate_comma(CHILD(tree, i));
-        else if (i != nch) {
-            ok = 0;
-            err_string("illegal trailing nodes for testlist_gexp");
-        }
-    }
-    return ok;
-}
-
-/*  decorator:
- *    '@' dotted_name [ '(' [arglist] ')' ] NEWLINE
- */
-static int
-validate_decorator(node *tree)
-{
-    int ok;
-    int nch = NCH(tree);
-    ok = (validate_ntype(tree, decorator) &&
-	  (nch == 3 || nch == 5 || nch == 6) &&
-	  validate_at(CHILD(tree, 0)) &&
-	  validate_dotted_name(CHILD(tree, 1)) &&
-	  validate_newline(RCHILD(tree, -1)));
-
-    if (ok && nch != 3) {
-	ok = (validate_lparen(CHILD(tree, 2)) &&
-	      validate_rparen(RCHILD(tree, -2)));
-
-	if (ok && nch == 6)
-	    ok = validate_arglist(CHILD(tree, 3));
-    }
-
-    return ok;
-}
-
-/*  decorators:
- *    decorator+
- */
-static int
-validate_decorators(node *tree)
-{
-    int i, nch, ok; 
-    nch = NCH(tree);
-    ok = validate_ntype(tree, decorators) && nch >= 1;
-
-    for (i = 0; ok && i < nch; ++i)
-	ok = validate_decorator(CHILD(tree, i));
-
-    return ok;
-}
-
-/*  funcdef:
- *      
- *            -6   -5    -4         -3  -2 -1
- *  [decorators] 'def' NAME parameters ':' suite
- */
-static int
-validate_funcdef(node *tree)
-{
-    int nch = NCH(tree);
-    int ok = (validate_ntype(tree, funcdef)
-	       && ((nch == 5) || (nch == 6))
-	       && validate_name(RCHILD(tree, -5), "def")
-	       && validate_ntype(RCHILD(tree, -4), NAME)
-	       && validate_colon(RCHILD(tree, -2))
-	       && validate_parameters(RCHILD(tree, -3))
-	       && validate_suite(RCHILD(tree, -1)));
-
-    if (ok && (nch == 6))
-	ok = validate_decorators(CHILD(tree, 0));
-
-    return ok;
-}
-
-
-static int
-validate_lambdef(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, lambdef)
-               && ((nch == 3) || (nch == 4))
-               && validate_name(CHILD(tree, 0), "lambda")
-               && validate_colon(CHILD(tree, nch - 2))
-               && validate_test(CHILD(tree, nch - 1)));
-
-    if (res && (nch == 4))
-        res = validate_varargslist(CHILD(tree, 1));
-    else if (!res && !PyErr_Occurred())
-        (void) validate_numnodes(tree, 3, "lambdef");
-
-    return (res);
-}
-
-
-static int
-validate_old_lambdef(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, old_lambdef)
-               && ((nch == 3) || (nch == 4))
-               && validate_name(CHILD(tree, 0), "lambda")
-               && validate_colon(CHILD(tree, nch - 2))
-               && validate_test(CHILD(tree, nch - 1)));
-
-    if (res && (nch == 4))
-        res = validate_varargslist(CHILD(tree, 1));
-    else if (!res && !PyErr_Occurred())
-        (void) validate_numnodes(tree, 3, "old_lambdef");
-
-    return (res);
-}
-
-
-/*  arglist:
- *
- *  (argument ',')* (argument [','] | '*' test [',' '**' test] | '**' test)
- */
-static int
-validate_arglist(node *tree)
-{
-    int nch = NCH(tree);
-    int i = 0;
-    int ok = 1;
-
-    if (nch <= 0)
-        /* raise the right error from having an invalid number of children */
-        return validate_numnodes(tree, nch + 1, "arglist");
-
-    if (nch > 1) {
-        for (i=0; i<nch; i++) {
-            if (TYPE(CHILD(tree, i)) == argument) {
-                node *ch = CHILD(tree, i);
-                if (NCH(ch) == 2 && TYPE(CHILD(ch, 1)) == gen_for) {
-                    err_string("need '(', ')' for generator expression");
-                    return 0;
-                }
-            }
-        }
-    }
-
-    while (ok && nch-i >= 2) {
-        /* skip leading (argument ',') */
-        ok = (validate_argument(CHILD(tree, i))
-              && validate_comma(CHILD(tree, i+1)));
-        if (ok)
-            i += 2;
-        else
-            PyErr_Clear();
-    }
-    ok = 1;
-    if (nch-i > 0) {
-        /*
-         * argument | '*' test [',' '**' test] | '**' test
-         */
-        int sym = TYPE(CHILD(tree, i));
-
-        if (sym == argument) {
-            ok = validate_argument(CHILD(tree, i));
-            if (ok && i+1 != nch) {
-                err_string("illegal arglist specification"
-                           " (extra stuff on end)");
-                ok = 0;
-            }
-        }
-        else if (sym == STAR) {
-            ok = validate_star(CHILD(tree, i));
-            if (ok && (nch-i == 2))
-                ok = validate_test(CHILD(tree, i+1));
-            else if (ok && (nch-i == 5))
-                ok = (validate_test(CHILD(tree, i+1))
-                      && validate_comma(CHILD(tree, i+2))
-                      && validate_doublestar(CHILD(tree, i+3))
-                      && validate_test(CHILD(tree, i+4)));
-            else {
-                err_string("illegal use of '*' in arglist");
-                ok = 0;
-            }
-        }
-        else if (sym == DOUBLESTAR) {
-            if (nch-i == 2)
-                ok = (validate_doublestar(CHILD(tree, i))
-                      && validate_test(CHILD(tree, i+1)));
-            else {
-                err_string("illegal use of '**' in arglist");
-                ok = 0;
-            }
-        }
-        else {
-            err_string("illegal arglist specification");
-            ok = 0;
-        }
-    }
-    return (ok);
-}
-
-
-
-/*  argument:
- *
- *  [test '='] test [gen_for]
- */
-static int
-validate_argument(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, argument)
-               && ((nch == 1) || (nch == 2) || (nch == 3))
-               && validate_test(CHILD(tree, 0)));
-
-    if (res && (nch == 2))
-        res = validate_gen_for(CHILD(tree, 1));
-    else if (res && (nch == 3))
-        res = (validate_equal(CHILD(tree, 1))
-               && validate_test(CHILD(tree, 2)));
-
-    return (res);
-}
-
-
-
-/*  trailer:
- *
- *  '(' [arglist] ')' | '[' subscriptlist ']' | '.' NAME
- */
-static int
-validate_trailer(node *tree)
-{
-    int nch = NCH(tree);
-    int res = validate_ntype(tree, trailer) && ((nch == 2) || (nch == 3));
-
-    if (res) {
-        switch (TYPE(CHILD(tree, 0))) {
-          case LPAR:
-            res = validate_rparen(CHILD(tree, nch - 1));
-            if (res && (nch == 3))
-                res = validate_arglist(CHILD(tree, 1));
-            break;
-          case LSQB:
-            res = (validate_numnodes(tree, 3, "trailer")
-                   && validate_subscriptlist(CHILD(tree, 1))
-                   && validate_ntype(CHILD(tree, 2), RSQB));
-            break;
-          case DOT:
-            res = (validate_numnodes(tree, 2, "trailer")
-                   && validate_ntype(CHILD(tree, 1), NAME));
-            break;
-          default:
-            res = 0;
-            break;
-        }
-    }
-    else {
-        (void) validate_numnodes(tree, 2, "trailer");
-    }
-    return (res);
-}
-
-
-/*  subscriptlist:
- *
- *  subscript (',' subscript)* [',']
- */
-static int
-validate_subscriptlist(node *tree)
-{
-    return (validate_repeating_list(tree, subscriptlist,
-                                    validate_subscript, "subscriptlist"));
-}
-
-
-/*  subscript:
- *
- *  '.' '.' '.' | test | [test] ':' [test] [sliceop]
- */
-static int
-validate_subscript(node *tree)
-{
-    int offset = 0;
-    int nch = NCH(tree);
-    int res = validate_ntype(tree, subscript) && (nch >= 1) && (nch <= 4);
-
-    if (!res) {
-        if (!PyErr_Occurred())
-            err_string("invalid number of arguments for subscript node");
-        return (0);
-    }
-    if (TYPE(CHILD(tree, 0)) == DOT)
-        /* take care of ('.' '.' '.') possibility */
-        return (validate_numnodes(tree, 3, "subscript")
-                && validate_dot(CHILD(tree, 0))
-                && validate_dot(CHILD(tree, 1))
-                && validate_dot(CHILD(tree, 2)));
-    if (nch == 1) {
-        if (TYPE(CHILD(tree, 0)) == test)
-            res = validate_test(CHILD(tree, 0));
-        else
-            res = validate_colon(CHILD(tree, 0));
-        return (res);
-    }
-    /*  Must be [test] ':' [test] [sliceop],
-     *  but at least one of the optional components will
-     *  be present, but we don't know which yet.
-     */
-    if ((TYPE(CHILD(tree, 0)) != COLON) || (nch == 4)) {
-        res = validate_test(CHILD(tree, 0));
-        offset = 1;
-    }
-    if (res)
-        res = validate_colon(CHILD(tree, offset));
-    if (res) {
-        int rem = nch - ++offset;
-        if (rem) {
-            if (TYPE(CHILD(tree, offset)) == test) {
-                res = validate_test(CHILD(tree, offset));
-                ++offset;
-                --rem;
-            }
-            if (res && rem)
-                res = validate_sliceop(CHILD(tree, offset));
-        }
-    }
-    return (res);
-}
-
-
-static int
-validate_sliceop(node *tree)
-{
-    int nch = NCH(tree);
-    int res = ((nch == 1) || validate_numnodes(tree, 2, "sliceop"))
-              && validate_ntype(tree, sliceop);
-    if (!res && !PyErr_Occurred()) {
-        res = validate_numnodes(tree, 1, "sliceop");
-    }
-    if (res)
-        res = validate_colon(CHILD(tree, 0));
-    if (res && (nch == 2))
-        res = validate_test(CHILD(tree, 1));
-
-    return (res);
-}
-
-
-static int
-validate_exprlist(node *tree)
-{
-    return (validate_repeating_list(tree, exprlist,
-                                    validate_expr, "exprlist"));
-}
-
-
-static int
-validate_dictmaker(node *tree)
-{
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, dictmaker)
-               && (nch >= 3)
-               && validate_test(CHILD(tree, 0))
-               && validate_colon(CHILD(tree, 1))
-               && validate_test(CHILD(tree, 2)));
-
-    if (res && ((nch % 4) == 0))
-        res = validate_comma(CHILD(tree, --nch));
-    else if (res)
-        res = ((nch % 4) == 3);
-
-    if (res && (nch > 3)) {
-        int pos = 3;
-        /*  ( ',' test ':' test )*  */
-        while (res && (pos < nch)) {
-            res = (validate_comma(CHILD(tree, pos))
-                   && validate_test(CHILD(tree, pos + 1))
-                   && validate_colon(CHILD(tree, pos + 2))
-                   && validate_test(CHILD(tree, pos + 3)));
-            pos += 4;
-        }
-    }
-    return (res);
-}
-
-
-static int
-validate_eval_input(node *tree)
-{
-    int pos;
-    int nch = NCH(tree);
-    int res = (validate_ntype(tree, eval_input)
-               && (nch >= 2)
-               && validate_testlist(CHILD(tree, 0))
-               && validate_ntype(CHILD(tree, nch - 1), ENDMARKER));
-
-    for (pos = 1; res && (pos < (nch - 1)); ++pos)
-        res = validate_ntype(CHILD(tree, pos), NEWLINE);
-
-    return (res);
-}
-
-
-static int
-validate_node(node *tree)
-{
-    int   nch  = 0;                     /* num. children on current node  */
-    int   res  = 1;                     /* result value                   */
-    node* next = 0;                     /* node to process after this one */
-
-    while (res && (tree != 0)) {
-        nch  = NCH(tree);
-        next = 0;
-        switch (TYPE(tree)) {
-            /*
-             *  Definition nodes.
-             */
-          case funcdef:
-            res = validate_funcdef(tree);
-            break;
-          case classdef:
-            res = validate_class(tree);
-            break;
-            /*
-             *  "Trivial" parse tree nodes.
-             *  (Why did I call these trivial?)
-             */
-          case stmt:
-            res = validate_stmt(tree);
-            break;
-          case small_stmt:
-            /*
-             *  expr_stmt | print_stmt | del_stmt | pass_stmt | flow_stmt
-             *  | import_stmt | global_stmt | exec_stmt | assert_stmt
-             */
-            res = validate_small_stmt(tree);
-            break;
-          case flow_stmt:
-            res  = (validate_numnodes(tree, 1, "flow_stmt")
-                    && ((TYPE(CHILD(tree, 0)) == break_stmt)
-                        || (TYPE(CHILD(tree, 0)) == continue_stmt)
-                        || (TYPE(CHILD(tree, 0)) == yield_stmt)
-                        || (TYPE(CHILD(tree, 0)) == return_stmt)
-                        || (TYPE(CHILD(tree, 0)) == raise_stmt)));
-            if (res)
-                next = CHILD(tree, 0);
-            else if (nch == 1)
-                err_string("illegal flow_stmt type");
-            break;
-          case yield_stmt:
-            res = validate_yield_stmt(tree);
-            break;
-            /*
-             *  Compound statements.
-             */
-          case simple_stmt:
-            res = validate_simple_stmt(tree);
-            break;
-          case compound_stmt:
-            res = validate_compound_stmt(tree);
-            break;
-            /*
-             *  Fundamental statements.
-             */
-          case expr_stmt:
-            res = validate_expr_stmt(tree);
-            break;
-          case print_stmt:
-            res = validate_print_stmt(tree);
-            break;
-          case del_stmt:
-            res = validate_del_stmt(tree);
-            break;
-          case pass_stmt:
-            res = (validate_numnodes(tree, 1, "pass")
-                   && validate_name(CHILD(tree, 0), "pass"));
-            break;
-          case break_stmt:
-            res = (validate_numnodes(tree, 1, "break")
-                   && validate_name(CHILD(tree, 0), "break"));
-            break;
-          case continue_stmt:
-            res = (validate_numnodes(tree, 1, "continue")
-                   && validate_name(CHILD(tree, 0), "continue"));
-            break;
-          case return_stmt:
-            res = validate_return_stmt(tree);
-            break;
-          case raise_stmt:
-            res = validate_raise_stmt(tree);
-            break;
-          case import_stmt:
-            res = validate_import_stmt(tree);
-            break;
-	  case import_name:
-	    res = validate_import_name(tree);
-	    break;
-	  case import_from:
-	    res = validate_import_from(tree);
-	    break;
-          case global_stmt:
-            res = validate_global_stmt(tree);
-            break;
-          case exec_stmt:
-            res = validate_exec_stmt(tree);
-            break;
-          case assert_stmt:
-            res = validate_assert_stmt(tree);
-            break;
-          case if_stmt:
-            res = validate_if(tree);
-            break;
-          case while_stmt:
-            res = validate_while(tree);
-            break;
-          case for_stmt:
-            res = validate_for(tree);
-            break;
-          case try_stmt:
-            res = validate_try(tree);
-            break;
-          case suite:
-            res = validate_suite(tree);
-            break;
-            /*
-             *  Expression nodes.
-             */
-          case testlist:
-            res = validate_testlist(tree);
-            break;
-          case yield_expr:
-            res = validate_yield_expr(tree);
-            break;
-          case testlist1:
-            res = validate_testlist1(tree);
-            break;
-          case test:
-            res = validate_test(tree);
-            break;
-          case and_test:
-            res = validate_and_test(tree);
-            break;
-          case not_test:
-            res = validate_not_test(tree);
-            break;
-          case comparison:
-            res = validate_comparison(tree);
-            break;
-          case exprlist:
-            res = validate_exprlist(tree);
-            break;
-          case comp_op:
-            res = validate_comp_op(tree);
-            break;
-          case expr:
-            res = validate_expr(tree);
-            break;
-          case xor_expr:
-            res = validate_xor_expr(tree);
-            break;
-          case and_expr:
-            res = validate_and_expr(tree);
-            break;
-          case shift_expr:
-            res = validate_shift_expr(tree);
-            break;
-          case arith_expr:
-            res = validate_arith_expr(tree);
-            break;
-          case term:
-            res = validate_term(tree);
-            break;
-          case factor:
-            res = validate_factor(tree);
-            break;
-          case power:
-            res = validate_power(tree);
-            break;
-          case atom:
-            res = validate_atom(tree);
-            break;
-
-          default:
-            /* Hopefully never reached! */
-            err_string("unrecognized node type");
-            res = 0;
-            break;
-        }
-        tree = next;
-    }
-    return (res);
-}
-
-
-static int
-validate_expr_tree(node *tree)
-{
-    int res = validate_eval_input(tree);
-
-    if (!res && !PyErr_Occurred())
-        err_string("could not validate expression tuple");
-
-    return (res);
-}
-
-
-/*  file_input:
- *      (NEWLINE | stmt)* ENDMARKER
- */
-static int
-validate_file_input(node *tree)
-{
-    int j;
-    int nch = NCH(tree) - 1;
-    int res = ((nch >= 0)
-               && validate_ntype(CHILD(tree, nch), ENDMARKER));
-
-    for (j = 0; res && (j < nch); ++j) {
-        if (TYPE(CHILD(tree, j)) == stmt)
-            res = validate_stmt(CHILD(tree, j));
-        else
-            res = validate_newline(CHILD(tree, j));
-    }
-    /*  This stays in to prevent any internal failures from getting to the
-     *  user.  Hopefully, this won't be needed.  If a user reports getting
-     *  this, we have some debugging to do.
-     */
-    if (!res && !PyErr_Occurred())
-        err_string("VALIDATION FAILURE: report this to the maintainer!");
-
-    return (res);
-}
-
-static int
-validate_encoding_decl(node *tree)
-{
-    int nch = NCH(tree);
-    int res = ((nch == 1)
-        && validate_file_input(CHILD(tree, 0)));
-
-    if (!res && !PyErr_Occurred())
-        err_string("Error Parsing encoding_decl");
-
-    return res;
-}
-
-static PyObject*
-pickle_constructor = NULL;
-
-
-static PyObject*
-parser__pickler(PyObject *self, PyObject *args)
-{
-    NOTE(ARGUNUSED(self))
-    PyObject *result = NULL;
-    PyObject *st = NULL;
-    PyObject *empty_dict = NULL;
-
-    if (PyArg_ParseTuple(args, "O!:_pickler", &PyST_Type, &st)) {
-        PyObject *newargs;
-        PyObject *tuple;
-
-        if ((empty_dict = PyDict_New()) == NULL)
-            goto finally;
-        if ((newargs = Py_BuildValue("Oi", st, 1)) == NULL)
-            goto finally;
-        tuple = parser_st2tuple((PyST_Object*)NULL, newargs, empty_dict);
-        if (tuple != NULL) {
-            result = Py_BuildValue("O(O)", pickle_constructor, tuple);
-            Py_DECREF(tuple);
-        }
-        Py_DECREF(empty_dict);
-        Py_DECREF(newargs);
-    }
-  finally:
-    Py_XDECREF(empty_dict);
-
-    return (result);
-}
-
-
-/*  Functions exported by this module.  Most of this should probably
- *  be converted into an ST object with methods, but that is better
- *  done directly in Python, allowing subclasses to be created directly.
- *  We'd really have to write a wrapper around it all anyway to allow
- *  inheritance.
- */
-static PyMethodDef parser_functions[] =  {
-    {"ast2tuple",       (PyCFunction)parser_st2tuple,  PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Creates a tuple-tree representation of an ST.")},
-    {"ast2list",        (PyCFunction)parser_st2list,   PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Creates a list-tree representation of an ST.")},
-    {"compileast",      (PyCFunction)parser_compilest, PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Compiles an ST object into a code object.")},
-    {"compilest",      (PyCFunction)parser_compilest,  PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Compiles an ST object into a code object.")},
-    {"expr",            (PyCFunction)parser_expr,      PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Creates an ST object from an expression.")},
-    {"isexpr",          (PyCFunction)parser_isexpr,    PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Determines if an ST object was created from an expression.")},
-    {"issuite",         (PyCFunction)parser_issuite,   PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Determines if an ST object was created from a suite.")},
-    {"suite",           (PyCFunction)parser_suite,     PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Creates an ST object from a suite.")},
-    {"sequence2ast",    (PyCFunction)parser_tuple2st,  PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Creates an ST object from a tree representation.")},
-    {"sequence2st",     (PyCFunction)parser_tuple2st,  PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Creates an ST object from a tree representation.")},
-    {"st2tuple",        (PyCFunction)parser_st2tuple,  PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Creates a tuple-tree representation of an ST.")},
-    {"st2list",         (PyCFunction)parser_st2list,   PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Creates a list-tree representation of an ST.")},
-    {"tuple2ast",       (PyCFunction)parser_tuple2st,  PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Creates an ST object from a tree representation.")},
-    {"tuple2st",        (PyCFunction)parser_tuple2st,  PUBLIC_METHOD_TYPE,
-        PyDoc_STR("Creates an ST object from a tree representation.")},
-
-    /* private stuff: support pickle module */
-    {"_pickler",        (PyCFunction)parser__pickler,  METH_VARARGS,
-        PyDoc_STR("Returns the pickle magic to allow ST objects to be pickled.")},
-
-    {NULL, NULL, 0, NULL}
-    };
-
-
-PyMODINIT_FUNC initparser(void);  /* supply a prototype */
-
-PyMODINIT_FUNC
-initparser(void)
-{
-    PyObject *module, *copyreg;
-
-    PyST_Type.ob_type = &PyType_Type;
-    module = Py_InitModule("parser", parser_functions);
-    if (module == NULL)
-    	return;
-
-    if (parser_error == 0)
-        parser_error = PyErr_NewException("parser.ParserError", NULL, NULL);
-
-    if (parser_error == 0)
-        /* caller will check PyErr_Occurred() */
-        return;
-    /* CAUTION:  The code next used to skip bumping the refcount on
-     * parser_error.  That's a disaster if initparser() gets called more
-     * than once.  By incref'ing, we ensure that each module dict that
-     * gets created owns its reference to the shared parser_error object,
-     * and the file static parser_error vrbl owns a reference too.
-     */
-    Py_INCREF(parser_error);
-    if (PyModule_AddObject(module, "ParserError", parser_error) != 0)
-        return;
-
-    Py_INCREF(&PyST_Type);
-    PyModule_AddObject(module, "ASTType", (PyObject*)&PyST_Type);
-    Py_INCREF(&PyST_Type);
-    PyModule_AddObject(module, "STType", (PyObject*)&PyST_Type);
-
-    PyModule_AddStringConstant(module, "__copyright__",
-                               parser_copyright_string);
-    PyModule_AddStringConstant(module, "__doc__",
-                               parser_doc_string);
-    PyModule_AddStringConstant(module, "__version__",
-                               parser_version_string);
-
-    /* Register to support pickling.
-     * If this fails, the import of this module will fail because an
-     * exception will be raised here; should we clear the exception?
-     */
-    copyreg = PyImport_ImportModule("copy_reg");
-    if (copyreg != NULL) {
-        PyObject *func, *pickler;
-
-        func = PyObject_GetAttrString(copyreg, "pickle");
-        pickle_constructor = PyObject_GetAttrString(module, "sequence2st");
-        pickler = PyObject_GetAttrString(module, "_pickler");
-        Py_XINCREF(pickle_constructor);
-        if ((func != NULL) && (pickle_constructor != NULL)
-            && (pickler != NULL)) {
-            PyObject *res;
-
-            res = PyObject_CallFunctionObjArgs(func, &PyST_Type, pickler,
-                                               pickle_constructor, NULL);
-            Py_XDECREF(res);
-        }
-        Py_XDECREF(func);
-        Py_XDECREF(pickle_constructor);
-        Py_XDECREF(pickler);
-        Py_DECREF(copyreg);
-    }
-}