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| From | Roger L Costello <costello@mitre.org> |
| Newsgroups | comp.compilers |
| Subject | Why is flex pattern-matching of NULs slow? |
| Date | Fri, 8 Apr 2022 11:06:00 +0000 |
| Organization | Compilers Central |
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| Posted-Date | 08 Apr 2022 11:48:17 EDT |
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Hi Folks,
The Flex manual says this:
Pattern-matching of NULs is substantially slower
than matching other characters.
Why is that?
/Roger
[My recollection is that zero is used as a flag value in internal
tables and there is some slow kludge to say that this is a nul not the
flag, but perhaps someone who has looked at the code more recently
will remember the details. -John]
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Why is flex pattern-matching of NULs slow? Roger L Costello <costello@mitre.org> - 2022-04-08 11:06 +0000 Why is flex pattern-matching of NULs slow? Christopher F Clark <christopher.f.clark@compiler-resources.com> - 2022-04-09 21:40 +0300
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