Current Path : /usr/local/lib/perl5/site_perl/5.8.9/Class/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
Current File : //usr/local/lib/perl5/site_perl/5.8.9/Class/ErrorHandler.pm |
# $Id: ErrorHandler.pm,v 1.1.1.1 2004/08/15 14:55:43 btrott Exp $ package Class::ErrorHandler; use strict; use vars qw( $VERSION $ERROR ); $VERSION = '0.01'; sub error { my $msg = $_[1] || ''; if (ref($_[0])) { $_[0]->{_errstr} = $msg; } else { $ERROR = $msg; } return; } sub errstr { ref($_[0]) ? $_[0]->{_errstr} : $ERROR } 1; __END__ =head1 NAME Class::ErrorHandler - Base class for error handling =head1 SYNOPSIS package Foo; use base qw( Class::ErrorHandler ); sub class_method { my $class = shift; ... return $class->error("Help!") unless $continue; } sub object_method { my $obj = shift; ... return $obj->error("I am no more") unless $continue; } package main; use Foo; Foo->class_method or die Foo->errstr; my $foo = Foo->new; $foo->object_method or die $foo->errstr; =head1 DESCRIPTION I<Class::ErrorHandler> provides an error-handling mechanism that's generic enough to be used as the base class for a variety of OO classes. Subclasses inherit its two error-handling methods, I<error> and I<errstr>, to communicate error messages back to the calling program. On failure (for whatever reason), a subclass should call I<error> and return to the caller; I<error> itself sets the error message internally, then returns C<undef>. This has the effect of the method that failed returning C<undef> to the caller. The caller should check for errors by checking for a return value of C<undef>, and calling I<errstr> to get the value of the error message on an error. As demonstrated in the L<SYNOPSIS>, I<error> and I<errstr> work as both class methods and object methods. =head1 USAGE =head2 Class->error($message) =head2 $object->error($message) Sets the error message for either the class I<Class> or the object I<$object> to the message I<$message>. Returns C<undef>. =head2 Class->errstr =head2 $object->errstr Accesses the last error message set in the class I<Class> or the object I<$object>, respectively, and returns that error message. =head1 LICENSE I<Class::ErrorHandler> is free software; you may redistribute it and/or modify it under the same terms as Perl itself. =head1 AUTHOR & COPYRIGHT Except where otherwise noted, I<Class::ErrorHandler> is Copyright 2004 Benjamin Trott, cpan@stupidfool.org. All rights reserved. =cut