Re: delimiters with more than one character? ...

From	John Crawley <john@bunsenlabs.org>
Newsgroups	linux.debian.user
Subject	Re: delimiters with more than one character? ...
Date	2020-08-07 03:10 +0200
Message-ID	<AAZ3s-QZ-3@gated-at.bofh.it> (permalink)
References	<AssHn-5be-3@gated-at.bofh.it> <AAl61-1NF-15@gated-at.bofh.it> <AArl8-5DY-17@gated-at.bofh.it> <AAEil-4Rk-3@gated-at.bofh.it> <AAMpC-1v6-3@gated-at.bofh.it>
Organization	BunsenLabs

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On 2020-08-06 20:33, Greg Wooledge wrote:
> For short strings, doing this sort of parsing in bash is fine.  But as
> you can see, on large inputs, it does not scale well.  The fact that each
> iteration makes a *copy* of nearly the entire remaining input doesn't
> help matters, either -- right off the bat, that algorithm makes the run
> time explode, even before you take into account bash's 100% interpreted
> runtime slowness.

Thanks for the insights.
So, re: the OP's question, it's possible in bash, but there's unlikely  
to be an efficient way for long strings.

But (unwilling to give up) IF it can be guaranteed that the string will  
never contain newlines, then this is about 16x faster than the  
snip-and-loop version:
---
#!/bin/bash

_S=' 34 + 45 \| abc \| 1 2 3 \| c\|123abc '
del='\|'

mapfile -t arr <<< ${_S//"${del}"/$'\n'}

declare -p arr
---
Seems to accept unusual characters and empty items.
Awk can ignore newlines, but a lot of the other shell tools are  
line-based anyway.

-- 
John

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Thread

delimiters with more than one character? ... Albretch Mueller <lbrtchx@gmail.com> - 2020-07-14 15:00 +0200
  Re: delimiters with more than one character? ... Alex Mestiashvili <amestia@rsh2.donotuse.de> - 2020-07-14 15:00 +0200
    Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-14 15:10 +0200
      Re: delimiters with more than one character? ... Nicolas George <george@nsup.org> - 2020-07-14 15:10 +0200
      Re: delimiters with more than one character? ... Alex Mestiashvili <amestia@rsh2.donotuse.de> - 2020-07-14 15:20 +0200
  Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-14 15:10 +0200
  Re: delimiters with more than one character? ... Nicolas George <george@nsup.org> - 2020-07-14 15:20 +0200
  Re: delimiters with more than one character? ... Nicolas George <george@nsup.org> - 2020-07-14 17:30 +0200
    Re: delimiters with more than one character? ... Albretch Mueller <lbrtchx@gmail.com> - 2020-07-15 12:30 +0200
      Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-15 14:00 +0200
      Re: delimiters with more than one character? ... David Wright <deblis@lionunicorn.co.uk> - 2020-07-15 14:30 +0200
      Re: delimiters with more than one character? ... Bob Weber <bobrweber@gmail.com> - 2020-07-15 14:40 +0200
        Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-15 14:50 +0200
          Re: delimiters with more than one character? ... Bob Weber <bobrweber@gmail.com> - 2020-07-15 16:20 +0200
            Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-15 16:30 +0200
            Re: delimiters with more than one character? ... The Wanderer <wanderer@fastmail.fm> - 2020-07-15 16:30 +0200
            Re: delimiters with more than one character? ... Nicolas George <george@nsup.org> - 2020-07-15 17:50 +0200
        Re: delimiters with more than one character? ... Nicolas George <george@nsup.org> - 2020-07-15 15:10 +0200
  Re: delimiters with more than one character? ... Bob Weber <bobrweber@gmail.com> - 2020-07-14 17:30 +0200
  Re: delimiters with more than one character? ... Alessandro Baggi <alessandro.baggi@gmail.com> - 2020-07-15 17:30 +0200
  Re: delimiters with more than one character? ... Eric S Fraga <e.fraga@ucl.ac.uk> - 2020-07-16 12:10 +0200
    Re: delimiters with more than one character? ... "Thomas Schmitt" <scdbackup@gmx.net> - 2020-07-16 13:40 +0200
      Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-16 14:00 +0200
        Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-16 16:00 +0200
          Re: delimiters with more than one character? ... Zenaan Harkness <zenaan@freedbms.net> - 2020-07-17 04:50 +0200
            Re: delimiters with more than one character? ... Nicolas George <george@nsup.org> - 2020-07-17 10:50 +0200
              Re: delimiters with more than one character? ... rhkramer@gmail.com - 2020-07-17 13:20 +0200
                tmpfs is not a ramdisk (was: delimiters with more than one  character? ...) Nicolas George <george@nsup.org> - 2020-07-17 13:30 +0200
                Re: tmpfs is not a ramdisk (was: delimiters with more than one  character? ...) David Wright <deblis@lionunicorn.co.uk> - 2020-07-17 18:20 +0200
                Re: tmpfs is not a ramdisk (was: delimiters with more than one character? ...) rhkramer@gmail.com - 2020-07-17 20:30 +0200
                Re: tmpfs is not a ramdisk (was: delimiters with more than one  character? ...) Zenaan Harkness <zenaan@freedbms.net> - 2020-07-18 07:20 +0200
                Re: tmpfs is not a ramdisk (was: delimiters with more than one  character? ...) <tomas@tuxteam.de> - 2020-07-18 10:40 +0200
                Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-17 13:40 +0200
        Re: delimiters with more than one character? ... "Thomas Schmitt" <scdbackup@gmx.net> - 2020-07-16 16:00 +0200
        Re: delimiters with more than one character? ... Zenaan Harkness <zenaan@freedbms.net> - 2020-07-17 04:50 +0200
      Re: delimiters with more than one character? ... Eric S Fraga <e.fraga@ucl.ac.uk> - 2020-07-16 15:00 +0200
  Re: delimiters with more than one character? ... John Crawley <john@bunsenlabs.org> - 2020-08-05 08:30 +0200
    Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-08-05 15:10 +0200
      Re: delimiters with more than one character? ... John Crawley <john@bunsenlabs.org> - 2020-08-06 05:00 +0200
        Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-08-06 13:40 +0200
          Re: delimiters with more than one character? ... John Crawley <john@bunsenlabs.org> - 2020-08-07 03:10 +0200

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