If you are offended by subroutine prototypes then look-away now.

This is an occasion where a prototype would have helped (OK, so there aren't that many of them):
Update: Doh! No it wouldn't, sorry. 
use strict;
use warnings;

sub processInterfaceData (\%\%)
{
  my ($h, $nh) = @_;

  foreach my $key (keys %{$h}) {
      print "$key\n";
  }
}

my %myUnitIfs;
my %config;
processInterfaceData($config{units}{myUnit}{interfaces}, %myUnitIfs);

[download]
Gives:
Type of arg 1 to main::processInterfaceData must be hash (not hash ele
+ment)

[download]
It gives the error as the calling line, not the subroutine, at compile time. Alos, because the caller does not specify the \ to indicate the reference, it is less likely for the problem to arise.

In reply to Re: Using foreach on a hash passed to a subroutine by cdarke
in thread Using foreach on a hash passed to a subroutine by carcassonne

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