Someone I work with started using the following "idiom" for passing arguments into a hash reference. He declared a hash reference and dereferences it within the "my" statement. 
use strict;

sub odd_args {
  my($this, %$args) = @_;
  print $args->{x},"\n";
}

odd_args(1, x => 2);

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I don't think he should have done it that way, but strangely enough, it worked in perl 5.6.1. It fails in perl 5.8.0. 

% perl5.6.1 qqq.pl
2

% /usr/local/bin/perl5.8.0 qqq.pl
Can't declare hash dereference in my at qqq.pl line 4, near ") ="
Execution of qqq.pl aborted due to compilation errors.

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Does anyone know what happened between perl 5.6.1 to open and then close this loophole?

In reply to Arg passing trick that fails in perl 5.8 by tall_man

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