Re: bug in elisp... or in elisper???

[David Kastrup]

ken <gebser@mousecar.com> writes:

> Fellow elispers,
>
> Something seems to be amiss in the search syntax here:
>
>  (setq aname-re-str
> "<a\\([\s-\\|\n]+?\\)name=\"\\(.*?\\)\"\\([\s-\\|\n]*?\\)>\\(\\(.\\|\n\\)*?\\)</a\\(\\(
> \\|\t\\|\n\\)*?\\)>" )
>
> ;;Here's a function to use the above RE and return diagnostics:
>
> (defun test-aname-search ()
>   (interactive)
>   (re-search-forward aname-re-str)
>   (message "1: \"%s\" 2: \"%s\" 3: \"%s\" 4: \"%s\" 5: \"%s\" 6: \"%s\"
> 7: \"%s\" 8: \"%s\""
>          (match-string 1)
>          (match-string 2)
>          (match-string 3)
>          (match-string 4)
>          (match-string 5)
>          (match-string 6)
>          (match-string 7)
>          (match-string 8)))
>
>
> The problem is that the 5th match-string should be either empty or
> whitespace.

Uh what?

\\(.\\|\n\\)*?

Matches _any_ character.

> But it consistently contains the last character of of the 4th
> match-string.

That is because it _is_ the last matched character of the 4th
match-string.

> And these two matches are separated by the literal
> character string, "</a"!!  What's up with this?

Your ability to count \\( strings?  They are assigned match numbers from
left to right, regardless of whether they are nested or not.

-- 
David Kastrup