package Mapx;

use strict;
use warnings;

use Exporter qw( import );
our @EXPORT = qw( mapx DONE_MAP );

use Scalar::Util qw( reftype blessed );

use constant DONE_MAP => \&mapx;

sub mapx(&@) {
   my $cb = shift;
   my @rv;
   for (@_) {
      my @x = $cb->();
      last if @x == 1 && reftype($x[0]) && !blessed($x[0]) && $x[0] ==
+ DONE_MAP;
      push @rv, @x;
   }
   return @rv;
}

1;

[download]
use strict;
use warnings;
use 5.010;

use Mapx;

sub x {
    my $target = shift;
    mapx {
         return DONE_MAP if $_ == $target;
         $_
    } @_;
}

say for x( 5, 1..9 );

[download]

In reply to Re: Short-circuiting a map list. by ikegami
in thread Short-circuiting a map list. by BrowserUk

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