package Explain::Plugin::NumberFormat; use Mojo::Base 'Mojolicious::Plugin'; sub register { my ( $self, $app ) = @_; # register helper $app->helper( commify_numbers => sub { my $self = shift; # Code taken from perlfaq5 local $_ = shift; return $_ unless defined $_; 1 while s/^([-+]?\d+)(\d{3})/$1,$2/; return $_; } ); } 1;