That is quite a generalization. The regex engine is tested, but my specific regular expression isn't. My ability to write correct regular expressions is weak, so there can be many bugs in the one line of regular expession.
If you have made a bug in the specification of the pattern to match, then you will have the same bug in the hand-rolled implementation of the matching. It will just be more difficult to find the bug since the pattern is not explicitly specified anymore.
bazoom42|10 months ago
unknown|10 months ago
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