doc: say that PCRE2_DFA_RESTART does not remove the need to retain data - #947
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NWilson merged 2 commits intoAug 16, 2026
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Thank you very much! I have made a couple of minor corrections, but your text is helpful. |
The multi-segment section explains the 1234|3789 limitation but leaves the impression that restarting frees the caller from keeping earlier text. A lookbehind still reaches back into it, and the bound is the same PCRE2_INFO_MAXLOOKBEHIND that the pcre2_match() section already describes. Wording follows what was concluded in PCRE2Project#867.
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Thanks for taking it and for the corrections 🙏🏼 rebased onto main, your commit kept as is. the red Bazel job on windows was a |
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Follow-up to #867
the multi-segment section for
pcre2_dfa_match()explains the1234|3789limitation, but it still reads as if restarting frees the caller from keeping earlier text. It does not: a lookbehind reaches back into the segment that was discarded, and the bound on how much to keep is the samePCRE2_INFO_MAXLOOKBEHINDthat thepcre2_match()section above already describesso the added paragraph says that, and points at retaining a bounded tail and running a fresh match as the approach that achieves the same results as searching the whole subject at once. Nothing new is claimed here, the wording follows what was concluded in #867
two files:
doc/pcre2partial.3, and the generateddoc/html/pcre2partial.htmlregenerated withmaint/132htmlthe waymaint/UpdateAlwayscalls it.maint/CheckManis clean on the pageif you would rather deprecate
PCRE2_DFA_RESTARToutright, say so and I will close this