Re: [External] : Re: Appending lists

[Emanuel Berg via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org>]

Jean Louis wrote:

>   ‘side-effect-free’ A non-‘nil’ value indicates that the
>   named function is free of side effects (*note What Is
>   a Function::), so the byte compiler may ignore a call
>   whose value is unused. If the property’s value is
>   ‘error-free’, the byte compiler may even delete such
>   unused calls. In addition to byte compiler optimizations,
>   this property is also used for determining function safety
>   (*note Function Safety::).
>
> Now... you could make a list of all functions and separate
> those with `side-effect-free' and those without, though
> I don't think it would guarantee the result.

No thanks, but it can be interesting to know and examine...

I didn't use `nbutlast', `delq', or `delete-dups', and
`remove' only once:

  (defun extract-strings (strings match)
    "From STRINGS, get a list with the parts that MATCH."
    (remove nil
      (mapcar
       (lambda (s) (when (string-match match s) (match-string 1 s)))
       strings) ))

Hm...

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