I use a slightly different, and probably slower, strategy for default arguments. I like it though, because it allows me to pass in multiple hashrefs. So it goes something like:
sub Whatever
{
# Optional test of the arguments. Good for catching programmer err
+ors.
# Not that anyone here ever makes any. 8-)
die 'Takes a hash ref' if @_ and grep { "HASH" ne ref } @_;
# Set up the defaults here:
my %args = ( KEY1 => 'default value', KEY2 => 'etc...' );
# And process the args.
my $index = @_; # Intentionally reverse the order.
# The first hash thus has precedence.
while( --$index >= $[ )
{
$args{$_} = $_[$index]->{$_} for keys %{$_[$index]}
}
# Do stuff with %args.
}
Also, instead of saying
keys, you could use an array of legal key values (using
uc or
lc to handle case issues) and then overwrite $arg{$legalkey} if it
exists in the passed in hash.
Note that I keep saying "passed in hash", what I should say is "hash that the passed in hashref references", but I'm lazy. Then again I added this comment... sigh