September 11, 2004
Reformed Perl - Third millenium syntax for Perl 5 OOP
One day I looked at all the hacks and detours necessary to have Perl perform the most basic OOP, and decided that I'm not going to take it anymore.
Enter Reformed Perl, a pragma that pulls Perl 5 OOP syntax into the year 2004. Here is a rundown of the things it does:
Shorthand inheritance
Rather than using the cumbersome use base 'Parent' you may write:
package Child < Parent;
Shorthand parameters
It is no longer necessary to fish method parameters out of @_:
sub method($foo, $bar)
{
print "First param: $foo";
print "Second param: $bar";
}
Implicit self, class and base
References to the instance, the class (package) and the base class
are implicitely provided as self, class and base:
sub method
{
self->instance_method();
class->static_method();
base->super_class_method();
}
Pretty field accessors
You may omit the curly brackets in self->{foo} if you declare
your field names using fields:
fields foo, bar;
sub method {
self->foo = "some value";
print self->foo;
}
You may intercept read and write access to instance fields by overwriting getter and setter methods:
fields foo;
sub get_foo
{
print "Getting foo!";
return self->{foo};
}
sub set_foo($value)
{
print "Setting foo!";
self->{foo} = $value;
}
Clean constructors
All reformed packages inherit a basic constructor new from the Class package.
When you need custom contructors, don't overwrite new - overwrite initialize:
use reform;
package Amy;
fields foo,
bar;
sub initialize($foo)
{
self->foo = $foo;
}
You may call the constructor of a base class by calling base->initialize().
