diff options
| author | Ori Bernstein <ori@eigenstate.org> | 2019-12-06 11:53:44 -0800 |
|---|---|---|
| committer | Ori Bernstein <ori@eigenstate.org> | 2019-12-06 11:53:44 -0800 |
| commit | 450ec696ee46f79159395a89c9a97bc8354616ba (patch) | |
| tree | 04ff35fcb03808d30b8ff88757627c888b923096 /sys/src/cmd/hoc | |
| parent | c3779afdd6452b40c27359a88af548e93635b595 (diff) | |
hoc: don't nest calls to follow() when lexing ++/+= and --/-= (#287)
The code had a nested use of the follow() function that could cause +=+
and -=- to register as ++ and --. The first follow() to execute could
consume a character and match and then the second follow() could consume
another character and match. For example i-=-10 would result in a syntax
error and i-=- would decrement i.
(imported from plan9port commit f1dd3f065a97f57bf59db2e3284868e181734159)
Diffstat (limited to 'sys/src/cmd/hoc')
| -rw-r--r-- | sys/src/cmd/hoc/hoc.y | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/sys/src/cmd/hoc/hoc.y b/sys/src/cmd/hoc/hoc.y index 673db5ae6..341202fe4 100644 --- a/sys/src/cmd/hoc/hoc.y +++ b/sys/src/cmd/hoc/hoc.y @@ -214,8 +214,8 @@ yylex(void) /* hoc6 */ return STRING; } switch (c) { - case '+': return follow('+', INC, follow('=', ADDEQ, '+')); - case '-': return follow('-', DEC, follow('=', SUBEQ, '-')); + case '+': return follow('+', INC, '+') == INC ? INC : follow('=', ADDEQ, '+'); + case '-': return follow('-', DEC, '-') == DEC ? DEC : follow('=', SUBEQ, '-'); case '*': return follow('=', MULEQ, '*'); case '/': return follow('=', DIVEQ, '/'); case '%': return follow('=', MODEQ, '%'); |