Hi monks,

I'm stumped by what seems to be a very basic thing. Using a hash ref inside a subroutine. I've tried several syntaxes but none worked so far, with results ranging from syntax errors to 'not a HASH reference' and such.

Here is the problem in a nutshell.

The idea is to be able to work on different parts of a large hash whose some of its 'subhashes' so to speak have the same structure. The result of that work is placed inside a hash taht contains already unit data, passed along to the subroutine. The work has to do with the interface sections of different types of units. 

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

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This would eventually be called on other units, with diffrenet new hashes to collect output:

processInterfaceData(\$config{units}{yourUnit}{interfaces}, \%yourUnit
+Ifs);
processInterfaceData(\$config{units}{anotherUnit}{interfaces}, \%anoth
+erUnitIfs);

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And here I've tried: $h, %$h, and many other variations.

sub processInterfaceData
{
  my ($h, $nh) = @_;
  print "$key\n"
   foreach my $key (keys %{$h});
}

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Pray tell, how one is to write the reference inside the subroutine so that elements of the hash are properly accessed ? - Thanks !

In reply to Using foreach on a hash passed to a subroutine by carcassonne

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