Re: regexp-quote missing escapes in grouping constructs - Bug?

[Miles Bader]

"St/n_P/rm/n" <address@hidden> writes:
> (regexp-quote "[0-9]\{2,4\}\(-\|/\)[0-9]?+\(-\|/\)[0-9]\{2,4\}")
>
> ---> "\\[0-9]{2,4}(-|/)\\[0-9]\\?\\+(-|/)\\[0-9]{2,4}"
>
> Am I misunderstanding something?

The backslashes you entered in the original lisp string were eaten by
the lisp reader, so there are no backslashes in the string.  Since (, ),
|, etc., are not emacs regexp metacharacters (without a preceding
backslash), there's no need to quote them.

Here's what you probably meant:

(regexp-quote "[0-9]\\{2,4\\}\\(-\\|/\\)[0-9]?+\\(-\\|/\\)[0-9]\\{2,4\\}")
=> 
"\\[0-9]\\\\{2,4\\\\}\\\\(-\\\\|/\\\\)\\[0-9]\\?\\+\\\\(-\\\\|/\\\\)\\[0-9]\\\\{2,4\\\\}"

-Miles

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