I have multiple classes defined in my main program. One is a parent class. The other are children classes:
# Main Program
...
package Foo; #Parent class
....
sub glob2regex {
my $glob = shift;
...here be dragons...
return $regex;
};
....
package Foo::Bar; #Child Class
base qw(Foo);
sub some_method {
my $self = shift;
my $regex = shift;
my $type = shift;
if ( $type eq "glob" ) {
$regex = glob2regex($regex); #ERROR: glob2regex is not defined.
}
...
}
I have a function in my parent class called glob2regex
. It isn't really a method because it doesn't do anything with the object. Instead, it's a helper function that my child classes can use.
However, calling it in my child class as shown above won't work because it's not defined in my child class. I could prepend the full parent class name on it (i.e. call it as Foo::glob2regex
instead of just glob2regex
), or I could modify it into an object, and call it as $self->glob2regex
. There maybe a even better way of handling this situation that I'm overlooking.
What is the best way to make a function like this that's defined in the parent class available in the child classes?
--
#! /usr/bin/env perl
#
use strict;
use warnings;
use feature qw(say);
use utf8;
########################################################################
# MAIN PROGRAM
my $bar = Foo::Bar->new;
$bar->just_foo_it;
#
########################################################################
########################################################################
#
package Foo;
sub lets_foo_it {
say "I've done foo!";
}
#
########################################################################
########################################################################
#
package Foo::Bar;
use base qw(Foo);
*Foo::Bar::lets_foo_it = *Foo::lets_foo_it;
sub new {
my $class = shift;
my $self = {};
bless $self, $class;
return $self;
}
sub just_foo_it {
my $self = shift;
lets_foo_it();
}
#
########################################################################
Exporting is usually done using Exporter.
BEGIN {
package Foo;
use Exporter qw( import );
our @EXPORT_OK = qw( glob2regex );
sub glob2regex { ... }
...
$INC{'Foo.pm'} = 1;
}
BEGIN {
package Foo::Bar;
use Foo qw( glob2regex );
our @ISA = 'Foo';
... glob2regex(...) ...
$INC{'Foo/Bar.pm'} = 1;
}
Note that it's very unusual for a class module to export subroutines. You should consider it a red flag indicating a likely design flaw.