Function::Register - Create Function Registries and Register Functions
package Company::Employee;
use Function::Register;
set_register 'Type';
sub employee_type {
my $self = shift;
for ( @Type ) {
my $retval = $_->($self);
return $retval if $retval;
}
return;
}
# meanwhile, in some other package
package Company::Employee::Executive;
use Function::Register 'Company::Employee';
register Type => \&is_cto;
register Type => \&is_ceo;
sub is_cto { ... }
sub is_ceo { ... }
# meanwhile, in your program
use Company::Employee;
use Company::Employee::Executive;
my $employee = Company::Employee->new( title => "CEO", ... );
print $employee->employee_type;
This module allows you to declare registers in your namespace, and update registers in other modules.
There are two ways to use this modules.
use Function::Register;
As the registry you simply use the module without any arguments. This will export the set_register function. It will also create a default register in your namespace called @REGISTER.
use Function::Register qw[Some::NameSpace];
As the registrant you use the module with a single argument. This will export the register function. It will remember what namespace you want to add to each time you call register.
set_registry 'Name';
This function creates a new register in your namespace. A register is a package array of the same name. The call above creates an array, @Name, in your namespace.
register sub { ... };
register Name => \&function_ref;
This function registeres functions in the namespace you've declared as your registrant. If a single argument is given the function is added to the default registry. If two arguments are given, the first is the name of of the register and the second is a function.
This function returns a false value if it was unable to add the function to the register. This may be because the register name does not exist, or the function argument isn't a code reference.
If register is successful it returns true.
die "Couldn't add to register"
unless register \&some_func;
For a more OO and "do it all for me behind my back" approach, see Module::Pluggable.
perl.
Casey West, <casey@geeknest.com>.
Copyright (c) 2004 Casey West. All rights reserved. This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
