in reply to runtime problem
Use :: instead of ->
if (my $numeral = Scalar::Util::looks_like_number($user_radius)) {
Scalar::Util does not have an object-oriented interface.
Similarly, you can also import the sub:
use Scalar::Util qw(looks_like_number); ... if (my $numeral = looks_like_number($user_radius)) {
In Section
Seekers of Perl Wisdom