in reply to Perl::Critic says don't modify $_ in list functions and other things

Sometimes, no loop is needed at all: 
chomp( my @list = <$fh> );

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When using readline, it's probably not so serious, as you aren't changing the original array in place at the same time.

The /r is useful when you want to keep the original: 

my @ids = map s/ /_/gr, 
          grep defined,
          @base;

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When you want to modify the original array, use "for" instead. 

for (@$list) {
    if (ref) {
        ...
    } else {
        $_ = ...;
    }
}

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map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

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Re^2: Perl::Critic says don't modify $_ in list functions and other things
by hippo (Archbishop) on Jul 09, 2020 at 08:33 UTC
    The /r is useful when you want to keep the original

    It is indeed useful and thanks for mentioning it (++). For some reason the fact that it exists never seems to stick with me! However, in Lady_Aleena's case it might not be an option because her sig says

    my perl versions are 5.28.1 local and 5.8.8 on web host.

    and /r only came in at 5.13.2 (according to perlver).

    As an even further aside it's a bit surprising to find anyone offering 5.8.8 as part of a service today. I am not aware of any O/S still shipping that as standard.

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      As an even further aside it's a bit surprising to find anyone offering 5.8.8 as part of a service today. I am not aware of any O/S still shipping that as standard.

      That's what I was thinking...
      I'm considering upgrading from shared hosting to VPS purely so I can upgrade from 5.16.003 to something a bit more modern. Being stuck with 5.8.8 seems a bit dire.

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        Your own VPS is so cheap these days, and allows the freedom to leave the past where it belongs. I'm sure you'll only have a positive experience moving forwards with this.

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