diff options
Diffstat (limited to 'ChangeLog')
| -rw-r--r-- | ChangeLog | 10 |
1 files changed, 10 insertions, 0 deletions
@@ -1,5 +1,15 @@ 2010-01-18 Kaz Kylheku <kkylheku@gmail.com> + * regex.c (reg_derivative_list, reg_derivative): Recognition + of cases to reduce consing. In reg_derivative_list, we avoid + consing the full or expression if either branch is t, and + also save a cons when the first element has a null derivative. + In reg_derivative the oneplus and zeroplus cases are split, + since zeroplus can re-use the input expression, when it's + just a one-character match, deriving nil. + +2010-01-18 Kaz Kylheku <kkylheku@gmail.com> + Adjust semantics of non-greedy operator R%S, to avoid the broken case whereby R%S matches nothing at all when S is not empty but equivalent to empty, or more generally when S is nullable. |