Ok, I guess I missed that particular point. Well, I think it is possible, but it's rather yucky and it suffers from the same problems that AutoLoader and the likes have. Basically, you compile your code in a two step process. First to compile the "import" routine. Then, when the import routine is called, the rest of the source is compiled Consider module Foo: 
package Foo;
require bytes; # make sure the module is loaded without (un)import

$bytes = 0;    # flag: whether bytes should be enforced
$evalled = 0;  # flag: whether rest of source has been compiled

sub import {
    unless ($evalled++) {               # we haven't evalled the rest 
+before
        $bytes = ($_[1] eq "usebytes"); # should bytes be enforced?
        local $/;                       # enable slurp mode
        eval <DATA>;                    # compile rest of source (afte
+r __DATA__)
        die $@ if $@;                   # die now if an error occurred
    }
};
1;                              # in order for require of Foo.pm to be
+ successful
__DATA__                        # actual source of module starts here
BEGIN {bytes->import if $bytes} # activate bytes if flag set
sub new { bless {},shift }      # example routine

[download]
Then, in an example program, you would do: 
use Foo 'usebytes'; # or something else to not use bytes
my $foo = Foo->new;

[download]
Hope this will help you in your quest.

Liz

In reply to Re: Re: Re: if only blocks were avoidable... by liz
in thread if only blocks were avoidable... by yosefm

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.