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Re: Help improve regular expression for 24 hours format
From: |
Jean Louis |
Subject: |
Re: Help improve regular expression for 24 hours format |
Date: |
Thu, 24 Nov 2022 13:31:00 +0300 |
User-agent: |
Mutt/2.2.7+37 (a90f69b) (2022-09-02) |
* tomas@tuxteam.de <tomas@tuxteam.de> [2022-11-24 12:40]:
> > Thanks, I make it now this way:
> >
> > (defvar rcd-rx-time (rx line-start (or "00" "01" "02" "03" "04" "05" "06"
> > "07" "08" "09" "10" "11"
> > "12" "13" "14" "15" "16" "17" "18" "19"
> > "20" "21" "22" "23")
> > ":" (any "0" "1" "2" "3" "4" "5") (any digit)
> > line-end)
> > "Regular expression for 24 hours format")
>
> Hm. By distributive law, (or (seq (any "01") (any digit)) (seq "2" (any
> "03")))
> should cover your hours part. And for the minutes's first digit, remember that
> `any' can do ranges: (any "0-5") resp. (any (?0 . ?5))
>
> > ➜ "^\\(?:0[0-9]\\|1[0-9]\\|2[0-3]\\):[0-5][[:digit:]]$"
>
> Even taking inspiration on what the "compiler" did of your expression might
> lead you to a simpler (and more readable!) expression, e.g.
>
> (or (seq "0" (any digit)) (seq "1" (any digit)) (seq "2" (any "0-3")))
>
> although slightly longer than my first proposal (perhaps the second is
> "quicker", but I'd let the regexp compiler sort that out: you are
> optimising for the human reader, after all).
Do you have completed example using:
(or (seq "0" (any digit)) (seq "1" (any digit)) (seq "2" (any "0-3"))) ?
--
Jean
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- Help improve regular expression for 24 hours format, Jean Louis, 2022/11/23
- Re: Help improve regular expression for 24 hours format, tomas, 2022/11/24
- Re: Help improve regular expression for 24 hours format, Yuri Khan, 2022/11/24
- Re: Help improve regular expression for 24 hours format, Jean Louis, 2022/11/24
- Re: Help improve regular expression for 24 hours format, tomas, 2022/11/24
- Re: Help improve regular expression for 24 hours format,
Jean Louis <=
- Re: Help improve regular expression for 24 hours format, tomas, 2022/11/24
- [SOLVED]: Re: Help improve regular expression for 24 hours format, Jean Louis, 2022/11/24
- [SOLVED]: Re: Help improve regular expression for 24 hours format, Jean Louis, 2022/11/24
- Re: [SOLVED]: Re: Help improve regular expression for 24 hours format, Emanuel Berg, 2022/11/26
- Re: [SOLVED]: Re: Help improve regular expression for 24 hours format, Jean Louis, 2022/11/26
Re: Help improve regular expression for 24 hours format, Michael Heerdegen, 2022/11/24