I had a similar problem, I wanted to create a sort function
that kept track of which attributes to use, so I used a closure:
sub sort_fun
{
# Get a has ref and and sort spec
my($hash_ref,$sort) = @_;
my @sort_columns = split(/[\|\,\+]/,$sort);
# Do some stuff...
# Create a closure function
return sub
{
# Test stuff...
foreach my $col (@sort_columns)
{
# lexically() is like an extended version of cmp
my $ret = lexically($hash_ref->{$a}->{$col},
$hash_ref->{$b}->{$col});
return $ret if($ret != 0);
}
return 0;
}
}
my $sort_fun = sort_fun(\%tracks,"year|name");
foreach my $id (sort $sort_fun keys(%tracks))
{
# Do something for every $id
}
The hardest part was creating a thing that sort
would accept as a function.