> What is or was the purpose of this construction? How would one use it?

#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

$_ = 'abacad';

say "/a(.)/";
if (/a(.)/g) {
    say "\$1: $1";
    say "\$&: $&";
} else {
    say 'No match';
}

for my $try (1 .. 3) {
    say "//";
    if (//g) {
        say "\$1: $1";
        say "\$&: $&";
    } else {
        say 'No match';
    }
}

[download]
Output: 
/a(.)/
$1: b
$&: ab
//
$1: c
$&: ac
//
$1: d
$&: ad
//
No match

[download]

Update: If I remember correctly, this was the original reason the feature was introduced: 

#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

my $x = 'found 11';
my $y = 'found 12';

if ($x =~ /found (\d+)/ && $y =~ //) {  # No need to repeat the long r
+egex! Yay!
    say "Found $1.";
}

[download]

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

In reply to Re^3: Empty pattern in regex by choroba
in thread Empty pattern in regex by choroba

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