bug#2881: 23.0.91; inconsistent regexps with "explicitly numbered group"
Joe Corneli <[email protected]>
| Newsgroups | gmane.emacs.bugs,gmane.emacs.pretest.bugs |
|---|---|
| Message-ID | <[email protected]> |
Oh, OK, I see! Never mind! On Fri, Apr 3, 2009 at 5:32 PM, Andreas Schwab <[email protected]> wrote: > Andreas Schwab <[email protected]> writes: > >> Joe Corneli <[email protected]> writes: >> >>> Please execute the following forms with C-x C-e. Form 1 >>> and Form 3 return `t' (Yes, we are looking at the >>> indicated regular expression), whereas Form 2 returns >>> `nil' (even though from the Elisp reference page "34.3.1.3 >>> Backslash Constructs in Regular Expressions", it appears >>> that this form ought to return `t' like the others). >> >> `\|' applies to the largest possible surrounding expressions. >> Only a surrounding `\( ... \)' grouping can limit the grouping >> power of `\|'. >> >>> (let ((possible-environments >>> "\\(?1:lisp\\)\\|\\(?1:idea\\)\\|\\(?1:common\\)") ) >>> (looking-at >>> (concat "\n*?\\\\begin{" >>> possible-environments >>> "}"))) >> >> >> The three alternatives of this regexp are "\n*?\\\\begin{\\(?1:lisp\\)", >> "\\(?1:idea\\)" and "\\(?1:common\\)". > > The last one is "\\(?1:common\\)}", of course. > > Andreas. > > -- > Andreas Schwab, [email protected] > GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5 > "And now for something completely different." >