Re: left-trim and right-trim for strings

[Stefan Monnier <address@hidden>]

How ironic.  You used `split-string' just where `string-match' makes
more sense and then use `string-match' where `split-string' is just what
you need:

> | (defun str-excessive-trim (str)
> |   "Return a string where all double-and-more whitespaces in STR are replaced
> | with a single space-character."
> |   (let ((s str))
> |     (while (string-match "[ \t][ \t]+" s)
> |       (setq s (concat (substring s 0 (match-beginning 0))
> |                       " "
> |                       (substring s (match-end 0)))))
> |     s))

How about (mapconcat 'identity " " (split-string str "[ \t][ \t]")) ?

> | (defun str-left-trim (str)
> |   "Return a string stripped of all leading whitespaces of STR."
> |   (or (car (split-string str "^[\n\t ]*")) ""))

Why not

   (if (string-match "\\`[\n\t ]+" str) (substring str (match-end 0)) str) ?
or
   (if (string-match "\\`[\n\t ]*" str) (substring str (match-end 0))) ?

> | (defun str-right-trim (str)
> |   "Return a string stripped of all trailing whitespaces of STR."
> |   (or (car (split-string str "[\n\t ]*$")) ""))

How about

  (substring str 0 (string-match "[\n\t ]*\\'" str))


-- Stefan