I'd like to get more information about my regexp matches. Specifically, I'd like to know the start and length (or equivalent information, of course) of the entire match, as well as any groups (/(...)/ constructs).

Emacs Lisp provides routines match-beginning, match-end and match-data to access this sort of information.

Currently I do something like this: 

$string =~ /^(.*?)($regexp)/;

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and then use length $1 and length $2 to give me the information I need. This is not a good way to do things; among other things, it shifts the numbers of any groupings in $regexp by 2 (this code is not responsible for $regexp).

And while I get information about the start and extent of the entire match, I don't get any information about the groups!

In reply to Getting information about regexp matches by ariels

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