Release of version 0.10 of Attribute::Types

NAME

Attribute::Types - Attributes that confer type on variables

VERSION

This document describes version 0.10 of Attribute::Types released May 10, 2001

DESCRIPTION

The Attribute::Types module provides 10 universally accessible attributes that can be used to create variables that accept assignments of only specific types of data.

EXAMPLES

use Attribute::Types;

        my $count   : INTEGER;           # Can only store an integer
        my $date    : INTEGER(1..31);    # Can only store an int between 1..31
        my $value   : NUMBER;            # Can only store a number
        my $score   : NUMBER(0.1..9.9);  # Can only store a num between 0.1..9.9
        my @rain    : NUMBER;            # Elements can only store numbers
        my %vars    : SCALAR;            # Entries can only store scalar refs
        my %handler : CODE;              # Entries can only store sub refs
        my $arr     : ARRAY;             # Can only store array ref
        my @hashes  : HASH;              # Elements can only store hash refs
        my $glob    : GLOB;              # Can only store a typeglob ref
        my $pattern : REGEX;             # Can only store a qr'd regex
        my $ref2    : REF;               # Can only store a meta-reference

        my $obj : Type(My::Class);       # Can only store objects of (or
                                         # derived from) the specified class

        my $x : Type(/good|bad|ugly/);   # Can only store strings matching
                                         # the specified regex

        sub odd { no warnings; $_[0]%2 }

        my $guarded : Type(&odd);        # Can only store values for which
                                         # odd($value) returns true

        $date = 23;                      # okay
        $date = 32;                      # KABOOM!

        $rain[1] = 121.7;                # okay
        $rain[1] = "lots";               # KABOOM!

        $x = 'very good';                # okay
        $x = 'excellent';                # KABOOM!

        package My::Class::Der;
        use base 'My::Class';

        $obj = My::Class->new();         # okay
        $obj = My::Class::Der->new();    # okay
        $obj = Other::Class->new();      # KABOOM!

        $guarded = 1;                    # okay
        $guarded = 2;                    # KABOOM!

AUTHOR

Damian Conway (damian@conway.org)

COPYRIGHT

             Copyright (c) 2001, Damian Conway. All Rights Reserved.
           This module is free software. It may be used, redistributed
          and/or modified under the terms of the Perl Artistic License
                (see http://www.perl.com/perl/misc/Artistic.html)

CHANGES IN VERSION 0.10

(No changes have been documented for this version)

AVAILABILITY

Attribute::Types has been uploaded to the CPAN and is also available from:

http://www.csse.monash.edu.au/~damian/CPAN/Attribute-Types.tar.gz