Re: A RE: SV: AW: "collapser", anyone...?

[Niklas Morberg <niklas.morberg@axis.com>]

Maciej Matysiak <phoner.ding@blah.pl> writes:

> the following regexp succeeded removing all the "re" variations from
> subject "Re[3]: Réf: Odp: SV[6]: Antw: blah", so i assume it works :)
>
> (setq message-subject-re-regexp
>       (concat
>        "^[ \t]*"
>          "\\("
>            "\\("
>              "\\([Aa][Nn][Tt][Ww]\\)\\|"              ; antw

Question: Are the parentheses really necessary? Isn't it
enough to say:

              "[Aa][Nn][Tt][Ww]\\|"              ; antw

I don't know.

>              "\\([Aa][Ww]\\)\\|"                      ; aw
>              "\\([Ff][Ww]d\\)\\|"                     ; fwd

The `d' is not always used. If it is, it is always (?) lower
case. Given that the `\\(' can be discarded this would be:

              "[Ff][Ww]d?\\|"                     ; fwd

>              "\\([Oo][Dd][Pp]\\)\\|"                  ; odp
>              "\\([Rr][Ee]\\)\\|"                      ; re
>              "\\([Rr]"                                ; réf
>                 (char-to-string (int-to-char '233))

Will this handle both upper and lower case (é and É)? I'm
not sure it's necessary, but since both `f' and `F' is
allowed maybe it should be there.

>              "[Ff]\\)\\|"
>              "\\([Ss][Vv]\\)"                         ; sv
>            "\\)"
>            "\\(\\[[0-9]*\\]\\)"
>            "*:[ \t]*"
>          "\\)"
>        "*[ \t]*"
>        ))

Breaking the regexp up made it much more readable, nice work.

Niklas