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Re: Experiences with match() subexpressions?

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In article <vt7qs4$2gior$1@dont-email.me>,
Janis Papanagnou  <janis_papanagnou+ng@hotmail.com> wrote:
>On 10.04.2025 09:06, Janis Papanagnou wrote:
>> I'm looking for subexpressions of regexp-matches using GNU Awk's
>> third parameter of match(). For example
>> 
>>   data = "R=r1,R=r2,R=r3,E=e"
>>   match (data, /^(R=([^,]+),){2,5}E=(.+)$/, arr)
>> 
>> The result stored in 'arr' seems to be determined by the static
>> parenthesis structure, so with the pattern repetition {2,5} only
>> the last matched data in the subexpression (r3) seems to persist
>> in arr. - I suppose there's no cute way to achieve what I wanted?
>
>To clarify; what I wanted is access of the values "r1", "r2", "r3",
>and "e" through 'arr'.

I have to admit that I (still) don't really understand how this match third
arg stuff works.  I.e., I can never predict what will happen, so I always
just dump out the array and try to reverse-engineer it each time I need to
use it.

I adapted your code into the following test script:

--- Cut Here ---
#!/bin/sh
gawk 'BEGIN {
    data = "R=r1,R=r2,R=r3,E=e"
    match (data, /^(R=([^,]+),){2,5}E=(.+)$/, arr)
    for (i in arr) print i,arr[i]
    }'

# To clarify; what I wanted is access of the values "r1", "r2", "r3",
# and "e" through 'arr'.
--- Cut Here ---

The output I get is:

--- Cut Here ---
0start 1
0length 18
3start 18
1start 11
2start 13
3length 1
2length 2
1length 5
0 R=r1,R=r2,R=r3,E=e
1 R=r3,
2 r3
3 e
--- Cut Here ---

After playing around a bit, I could not come up with any sensible way of
getting what you want to get.

As an alternative, it sounds like you could just could just split the
string on the comma; that would get you:

    R=r1
    R=r2
    R=r3
    E=e

Or, for finer control, you could use patsplit().

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Experiences with match() subexpressions? Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-10 09:06 +0200
  Re: Experiences with match() subexpressions? Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-10 09:09 +0200
    Re: Experiences with match() subexpressions? gazelle@shell.xmission.com (Kenny McCormack) - 2025-04-10 11:08 +0000
      Re: Experiences with match() subexpressions? Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-10 13:55 +0200
        Re: Experiences with match() subexpressions? gazelle@shell.xmission.com (Kenny McCormack) - 2025-04-10 14:04 +0000
          Re: Experiences with match() subexpressions? Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-10 23:39 +0200
            Re: Experiences with match() subexpressions? arnold@freefriends.org (Aharon Robbins) - 2025-04-11 06:33 +0000
              Re: Experiences with match() subexpressions? Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-11 09:10 +0200
                Re: Experiences with match() subexpressions? Kaz Kylheku <643-408-1753@kylheku.com> - 2025-04-11 08:22 +0000
                Re: Experiences with match() subexpressions? Manuel Collado <mcollado2011@gmail.com> - 2025-04-18 12:03 +0200
                Re: Experiences with match() subexpressions? gazelle@shell.xmission.com (Kenny McCormack) - 2025-04-18 12:01 +0000
                Re: Experiences with match() subexpressions? Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-18 14:24 +0200
              Re: Experiences with match() subexpressions? Kaz Kylheku <643-408-1753@kylheku.com> - 2025-04-11 07:40 +0000
              The new matcher (Was: Experiences with match() subexpressions?) gazelle@shell.xmission.com (Kenny McCormack) - 2025-04-11 08:57 +0000
                Re: The new matcher (Was: Experiences with match() subexpressions?) Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-11 15:50 +0200
              Re: Experiences with match() subexpressions? Kaz Kylheku <643-408-1753@kylheku.com> - 2025-04-11 17:54 +0000
    Re: Experiences with match() subexpressions? Ed Morton <mortonspam@gmail.com> - 2025-04-10 20:07 -0500
      Re: Experiences with match() subexpressions? Ed Morton <mortonspam@gmail.com> - 2025-04-13 12:52 -0500
        Nitpicking the code (Was: Experiences with match() subexpressions?) gazelle@shell.xmission.com (Kenny McCormack) - 2025-04-14 18:20 +0000
          Re: Nitpicking the code (Was: Experiences with match() subexpressions?) Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-14 20:53 +0200
            Re: Nitpicking the code (Was: Experiences with match() subexpressions?) Ed Morton <mortonspam@gmail.com> - 2025-04-14 18:55 -0500
              Re: Nitpicking the code (Was: Experiences with match() subexpressions?) Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-15 05:35 +0200

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