lopping through a hash passed as a reference

mnlight has asked for the wisdom of the Perl Monks concerning the following question:

I have created a hash in one subroutine and then pass it to a second subroutine as a reference. I want to loop through the hash and process each element one by one. here is how I tested it. %hash is not recognized.

sub loop_through_hash{
my($hash) = @_;
foreach $k (keys %hash){
print "$k => $hash{$k}
}#end foreach loop
}#end loop_through_hash
[download]

Comment on lopping through a hash passed as a reference Download Code

Replies are listed 'Best First'.
Re: lopping through a hash passed as a reference by vek (Prior) on Oct 25, 2002 at 15:38 UTC
Try this: `foreach $k (keys %$hash) { print $k, "=>", $hash->{$k}, "\n"; }` [download] -- vek --	[reply] [d/l]
Re: Re: lopping through a hash passed as a reference by mnlight (Scribe) on Oct 25, 2002 at 15:44 UTC
perfect	[reply]
Re: lopping through a hash passed as a reference by VSarkiss (Monsignor) on Oct 25, 2002 at 15:40 UTC
Very close. Try this instead: `foreack $k (keys %$hash) { print "$k => $hash->{$k}\n"; print "$k => $$hash{$k}\n"; # equivalent }` [download] The code you have above is for a hash named `%hash`, not a reference to a hash contained in a scalar `$hash`. Notice that in the code above, the sigil preceding the variable is always a `$`. For more info on references in general, take a look at perlref and perlreftut.	[reply] [d/l] [select]