Re: can I change hash keys or values directly

I came here to this thread to give my answer for your question. After reading the responses given by other monks I found out that absolutely the same answer has already been given by choroba. The code below is just example of the suggestion by choroba and mine.

#!/usr/bin/env perl

use strict;
use warnings;
use Data::Dumper;

my $x = { a => [ 1, 2 ], c => [ qw( a b c ) ], d => 100 };
print 'original: ', Dumper $x;

# one by one replacement: c -> b, d -> c
$x->{b} = delete $x->{c};
$x->{c} = delete $x->{d};
print 'modified: ', Dumper $x;

# in one run replacement: b, c -> c, d
@$x{qw( c d )} = delete @$x{qw( b c )};
print 'reverted: ', Dumper $x;
[download]

Comment on Re: can I change hash keys or values directly Download Code

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Re^2: can I change hash keys or values directly by misterperl (Friar) on Jan 29, 2021 at 14:27 UTC
I appreciate the replies guys. I guess I was already on the best approach using the slice. The link to "values" and it's helpful to know that they be operated on directly. I tried it `map s.(\d+).$1+1/e,values %nums;` [download] which worked great. Love it. Helpful & useful. TYVM If I'm reading that right, it does appear from that link that as an experiment, perhaps keys also worked that way for some brief Perl versions: `use 5.012; # so keys/values/each work on arrays` [download]	[reply] [d/l] [select]
Re^3: can I change hash keys or values directly by choroba (Cardinal) on Jan 29, 2021 at 22:44 UTC
> perhaps keys also worked that way No, it means you can write `#!/usr/bin/perl use warnings; use strict; use feature qw{ say }; use Syntax::Construct qw{ keys-array }; # More explicit than 5.012. my @array = qw( abc def ); my @keys = keys @array; # 0, 1 my @values = values @array; # abc, def while (my ($index, $value) = each @array) { say "$index $value"; # 0 abc, 1 def }` [download] `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^ARGV,3]`	[reply] [d/l] [select]