MeowChow's code for passing by reference is VERY inefficient unless you actually want a copy of the Hash. (Why pass by ref if you want a copy?) 
  mysub(\%hash);

  sub mysub {

    my $paramhash = $_[0];
  }

[download]
With the above code any modification will affect the original hash.

In reply to Re: How Do I pass a hash to a subroutine? by thephpguy
in thread How Do I pass a hash to a subroutine? by filmo

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