How do I dereference a Perl hash reference that's been passed to a subroutine?

perl hash dereference
sgsax picture sgsax · Feb 17, 2010 · Viewed 13.7k times · Source

I'm still trying to sort out my hash dereferencing. My current problem is I am now passing a hashref to a sub, and I want to dereference it within that sub. But I'm not finding the correct method/syntax to do it. Within the sub, I want to iterate the hash keys, but the syntax for a hashref is not the same as a hash, which I know how to do.

So what I want is to do this:

sub foo {
    %parms = @_;
    foreach $keys (key %parms) { # do something };
}

but with a hashref being passed in instead of a hash.

Any pointers (pun not intended) are welcome.

Thanks.

Answer

cyberconte picture cyberconte · Feb 17, 2010

I havn't actually tested the code at this time, but writing freehand you'll want to do something like this:

sub foo {
    $parms = shift;
    foreach my $key (keys %$parms) { # do something };
}

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