package Evaled::INIT;

use 5.008;
use strict;
use warnings;

our $VERSION = '0.01';

my $filter;

use Filter::Simple sub 
{
    return if $filter++;
    
    my $i=0;
    while ( $_ =~ s/(^|[\s\t;}])INIT(?!\x00)([\s\n]*|{)/$1INIT\x00 { \
+&SINIT$i; } \nsub SINIT$i$2/ms ) {$i++;};     
    s/\x00//msg;
};

1;

__END__

=head1 NAME

Evaled::INIT - Perl extension for executing INIT-sections

=head1 SYNOPSIS

  use Evaled::INIT;

=head1 ABSTRACT

When you I<use> a module in an I<eval()>-statement,
then the modules I<INIT>-sections (if any) are not executed. This modu
+le can be used to work-around this behaviour.

=head2 VERSION

This is Version 0.1, early beta-state ,-)

=head1 DESCRIPTION

When you I<use> a module in an I<eval()>-statement, like

  $mod = "Foo";
  eval "use $mod;";

then the modules I<INIT>-sections (if any) are not executed.

Such statements may be used to load unknown modules at runtime,
or might be implicitly caused by an environment like the I<Windows Scr
+ipting Host (WSH)> or mod_perl.
Such a WSH-PerlSript is always executed within an I<eval()>.

This behaviour can cause the module to act irregularly.
If you need to use such a module in any I<eval>-statement you can you 
+use this module to work around.

Simply add the line 

  use Evaled::INIT;

at the top of the modules code (right after the I<package xxx;>-statem
+ent).
I<Evaled::INIT> acts as a source-filter. 

B<Hint:>
I<A source-filter is a module that can change the sourcecode of the mo
+dule that uses it to 
whatever the filter wants. This happens before the modules code is com
+piled.>

In this case the filter will replace all 
  
  INIT 
  { 
    #do something
  }

with 

  INIT 
  {
    &SINITx();
  }
  
  sub SINITx
  { 
    #do something
  }

where I<x> is the number of the I<BEGIN>-section (there can be more th
+an one) in top-down-order,
starting with 0.
After that conversion you can call the I<SINITx>-Functions as apropria
+te, like

  $mod = "Foo";
  eval "use $mod;";
  eval "&$mod::SINITx();";

=head2 EXPORT

None by default or query.

=head2 EXAMPLES

=head3 Bad example, INIT is not executed.

  #File t.pm
  INIT
  {
    print "INIT\n";
  }
  
  1;
  
  #File t.pl
  eval "use t.pm;";
  print "main\n";

Output:

  >>perl t.pl
  main
  >>

=head3 Good example, INIT can be called.

  #File t.pm
  use Evaled::INIT;
  
  INIT
  {
    print "INIT\n";
  }
  
  1;
  
  #File t.pl
  eval "use t.pm; &t::SINIT0();";
  print "main\n";

Output:

  >>perl t.pl
  INIT
  main
  >>

=head3  Good example, INIT still works

  #of course the module will still work without eval

  #File t.pm
  use Evaled::INIT;
  
  INIT
  {
    print "INIT\n";
  }
  
  1;
  
  #File t.pl
  use t.pm;
  print "main\n";

Output:

  >>perl t.pl
  INIT
  main
  >>
  


=head1 AUTHOR

Markus Holzer (m.holzer/at/kvsaarland.de)

=head1 COPYRIGHT AND LICENSE

This library is free software; you can redistribute it and/or modify i
+t under the same terms as Perl itself. 

=cut
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