Use a prototype. Here is an example from Graham Barr's List::Util: 
sub first (&@) {
  my $code = shift;

  foreach (@_) {
    return $_ if &{$code}();
  }

  undef;
}

[download]
which is invoked as 
# first defined value in @list
$foo = first { defined($_) } @list;

[download]
-Mark

In reply to Re: How do I write subs that take bare blocks as args? by kvale
in thread How do I write subs that take bare blocks as args? by DamnDirtyApe

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