Thank you. That indeed dispels my brain fog! Best, Bert
Bert Gunter "The trouble with having an open mind is that people keep coming along and sticking things into it." -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) On Wed, Aug 12, 2020 at 6:35 AM Stefan Evert <stefa...@collocations.de> wrote: > > > On 10 Aug 2020, at 18:36, Bert Gunter <bgunter.4...@gmail.com> wrote: > > > > But this appears to be imprecise (it confused me, anyway). The usual > sense > > of "matching" in regex's is "match the pattern somewhere in the string > > going forward." But in the perl lookahead construct it apparently must > > **exactly** match *everything* in the string that follows. > > > > Questions: > > Am I correct about this? If not, what do I misunderstand? > > I think you're confused about the terminology. To _match_ a regular > expression is to find a substring described by the regexp at a given > starting point; what you have in mind is to _search_ a string for matches > of a regular expression. > > Python uses this terminology in its regexp matching functions, and from > what you cited in the documentation so do Perl and PCRE in their docs. > > Best, > Stefan > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
