Re^2: Finding hashes in hashes of hashes

[cyphy]

Thanks for you answer. It solves my problem! No, it is not my homework (got something else). I'm just trying to create a script where I need something similar (no families and no flinstones ;). I didn't want to write the full code, since I only need this in a single sub. I am using strict, warnings, diagnostics and even perlcritic (cruel). I played around with something like this:

get_family_member('bart',$families);

sub get_family_member {
  my @args = @_;
  my $who = shift @args;
  my $families = shift @args;
  foreach my $family (%families) {
    if ($families->{$family}->{kid} eq "bart") {
      return $dfamilies->{$family}->{kid};
      last;
    }
  }
}

but where would I say, it should die, when 'bart' is not found? It has been a while since I used perl the last time. I returned, because I missed the nice community and CPAN. However, since I used some more exotic languages (far away from C-like styles and paradigms) I guess I need to rewire my brain. I hope I remember correctly, how Perls scopes and datatypes work. Maybe I should just try to find my old perl books.

[bobf]

The 'die' would go after the foreach (refer to the pseudocode that I posted). Note the comments below:

sub get_family_member {
  my @args = @_;
  my $who = shift @args; # <-- this var is not used
  my $families = shift @args;
  foreach my $family (%families) {
    if ($families->{$family}->{kid} eq "bart") { # <-- are you sure yo
+u want to hard-code 'bart'? I think you need $who
      return $dfamilies->{$family}->{kid}; # <-- typo in hash name
      last; # <-- this will never be reached since it already returned
    }
  }

  # no matches found:  die here
}

[AnomalousMonk]

bobf is quite right: the statements
    my @args = @_;
    my $who = shift @args;
    my $families = shift @args;
are much better written as
    my ($who, $families) = @_;


Also,  $families in the above example seems to be a hash reference,
so use  %$families to dereference.

Further,
    for my $family (%$families) { ... }
won't do what you want; use
    for my $family (keys %$families) { ... }
to iterate over the keys of the referenced hash.

[cyphy]

Thank you! About the typo and the who.. This is what happens, when you try to change your code to only reflect relevant parts. Next time I'll simply copy it.