4 ms·
Alternate representations of regexes aren't necessarily a crutch to avoid learning the normal syntax. S-expressions in particular could be useful for runtime ma
by skymt 12y ago
Alternate representations of regexes aren't necessarily a crutch to avoid learning the normal syntax. S-expressions in particular could be useful for runtime manipulation or generation of patterns without the bother of string mangling. (I can't think of a reason to do so off-hand, but it's a nifty capability.)
- to3m 12y agoHere's an example of this kind of thing from some emacs lisp I wrote (which I hope survived the transition to the HN comment box): (setq imenu-generic-expression (let ((ident '(1+ (any "A-Za-z0-9_")))) `(("plugin" ,(rx line-start (0+ space) "plugin" (1+ space) (eval ident) (1+ space) (group (eval ident))) 1)))) Of course, you can do this with string concatenation, but I think this syntax makes it clearer what's going on.