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|
package Module::Load;
$VERSION = '0.18';
use strict;
use File::Spec ();
sub import {
my $who = _who();
{ no strict 'refs';
*{"${who}::load"} = *load;
}
}
sub load (*;@) {
my $mod = shift or return;
my $who = _who();
if( _is_file( $mod ) ) {
require $mod;
} else {
LOAD: {
my $err;
for my $flag ( qw[1 0] ) {
my $file = _to_file( $mod, $flag);
eval { require $file };
$@ ? $err .= $@ : last LOAD;
}
die $err if $err;
}
}
### This addresses #41883: Module::Load cannot import
### non-Exporter module. ->import() routines weren't
### properly called when load() was used.
{ no strict 'refs';
my $import;
if (@_ and $import = $mod->can('import')) {
unshift @_, $mod;
goto &$import;
}
}
}
sub _to_file{
local $_ = shift;
my $pm = shift || '';
my @parts = split /::/;
### because of [perl #19213], see caveats ###
my $file = $^O eq 'MSWin32'
? join "/", @parts
: File::Spec->catfile( @parts );
$file .= '.pm' if $pm;
### on perl's before 5.10 (5.9.5@31746) if you require
### a file in VMS format, it's stored in %INC in VMS
### format. Therefor, better unixify it first
### Patch in reply to John Malmbergs patch (as mentioned
### above) on p5p Tue 21 Aug 2007 04:55:07
$file = VMS::Filespec::unixify($file) if $^O eq 'VMS';
return $file;
}
sub _who { (caller(1))[0] }
sub _is_file {
local $_ = shift;
return /^\./ ? 1 :
/[^\w:']/ ? 1 :
undef
#' silly bbedit..
}
1;
__END__
=pod
=head1 NAME
Module::Load - runtime require of both modules and files
=head1 SYNOPSIS
use Module::Load;
my $module = 'Data:Dumper';
load Data::Dumper; # loads that module
load 'Data::Dumper'; # ditto
load $module # tritto
my $script = 'some/script.pl'
load $script;
load 'some/script.pl'; # use quotes because of punctuations
load thing; # try 'thing' first, then 'thing.pm'
load CGI, ':standard' # like 'use CGI qw[:standard]'
=head1 DESCRIPTION
C<load> eliminates the need to know whether you are trying to require
either a file or a module.
If you consult C<perldoc -f require> you will see that C<require> will
behave differently when given a bareword or a string.
In the case of a string, C<require> assumes you are wanting to load a
file. But in the case of a bareword, it assumes you mean a module.
This gives nasty overhead when you are trying to dynamically require
modules at runtime, since you will need to change the module notation
(C<Acme::Comment>) to a file notation fitting the particular platform
you are on.
C<load> eliminates the need for this overhead and will just DWYM.
=head1 Rules
C<load> has the following rules to decide what it thinks you want:
=over 4
=item *
If the argument has any characters in it other than those matching
C<\w>, C<:> or C<'>, it must be a file
=item *
If the argument matches only C<[\w:']>, it must be a module
=item *
If the argument matches only C<\w>, it could either be a module or a
file. We will try to find C<file.pm> first in C<@INC> and if that
fails, we will try to find C<file> in @INC. If both fail, we die with
the respective error messages.
=back
=head1 Caveats
Because of a bug in perl (#19213), at least in version 5.6.1, we have
to hardcode the path separator for a require on Win32 to be C</>, like
on Unix rather than the Win32 C<\>. Otherwise perl will not read its
own %INC accurately double load files if they are required again, or
in the worst case, core dump.
C<Module::Load> cannot do implicit imports, only explicit imports.
(in other words, you always have to specify explicitly what you wish
to import from a module, even if the functions are in that modules'
C<@EXPORT>)
=head1 ACKNOWLEDGEMENTS
Thanks to Jonas B. Nielsen for making explicit imports work.
=head1 BUG REPORTS
Please report bugs or other issues to E<lt>bug-module-load@rt.cpan.org<gt>.
=head1 AUTHOR
This module by Jos Boumans E<lt>kane@cpan.orgE<gt>.
=head1 COPYRIGHT
This library is free software; you may redistribute and/or modify it
under the same terms as Perl itself.
=cut
|
