On Wed, May 22 2024, Philip Kaludercic wrote:
> Joost Kremers <joostkremers@fastmail.fm> writes:
>> +(defun csv--unquote-value (value)
>> +  "Remove quotes around VALUE.
>> +If VALUE contains escaped quote characters, un-escape them.  If
>> +VALUE is not quoted, return it unchanged."
>> +  (save-match-data
>> +    (let ((quote-regexp (apply #'concat `("[" ,@csv-field-quotes "]"))))
>> +      (string-match (concat "^\\(" quote-regexp "\\)\\(.*\\)\\(" quote-regexp "\\)$") value)
>
> Shouldn't this `string-match' be in the if-let?

I considered that, but in this particular case, `(match-string 1 value)` returns
nil if the first character of `value` isn't in `csv-field-quotes`, so it seems
to be OK.

Emphasis on "seems" though... Plus, there's no need to call `match-string` at
all if `string-match` failed, of course. So new patch attached.

> Take this example,
>
> (let ((str "1 2 3"))
>   (list (string-match "2" str)
> 	(match-string 0 str)
> 	(string-match "4" str)
> 	(match-string 0 str)))
> ;;=> (2 "2" nil "2")
>
> even though string-match failed, the match data remains and matc-string
> returns non-nil values.

Oh... I kinda assumed that `string-match` would always reset all of the match
data, but apparently not. Good to know!


Thanks,

Joost


-- 
Joost Kremers
Life has its moments