(bbfu) (just to confuse the issue) Re(2): use strict and exporting package variables

You could, of course, put the lexical variables into the symbol table. Exporter doesn't do this, and I'm still even mostly sure that it's better that way.

Some code (and it demonstrates how import() works, too):

In test.pl:

use MyTest;
print "Once-lexical variable holds $lexvar\n";
[download]

In MyTest.pm:

package MyTest;

my $lexvar = 7;

# This function is called automatically whenever
# anyone 'use's (or 'require's, I'm pretty sure)
# our module.  Note that this happens at COMPILE TIME.
sub import {
  # symbol table manipulation usually requires
  # the use of symbolic references...
  no strict 'refs';

  # Figure out where to export to.
  # Check `perldoc -f caller` for info on caller.
  my $pkg_to_export_to = (caller)[0];

  # Make the scalar part of the entry in the symbol
  # table of the calling package for 'lexvar' into a hard
  # reference to our lexical variable.  This is called
  # typeglob aliasing.
  *{$pkg_to_export_to . '::lexvar'} = \$lexvar;
}
[download]

Okay, maybe I'm just sick. ;-)

bbfu
Seasons don't fear The Reaper.
Nor do the wind, the sun, and the rain.
We can be like they are.

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(tye)Re: (bbfu) (just to confuse the issue) Re(2): use strict and exporting package variables by tye (Sage) on May 01, 2001 at 09:39 UTC
FYI, Exporter can't do that since its code is in a different file and therefore has no access to the lexical variables in your module's file. - tye (but my friends call me "Tye")	[reply]
(bbfu) (Re(2): tye) (just to confuse the issue) Re(2): use strict and exporting package variables by bbfu (Curate) on May 01, 2001 at 10:30 UTC
I know that. :-P What I was thinking of, though I didn't actually say it, was some sort of mechanism where you would pass it a reference to a lexical variable that it would then export into the caller's symbol table. I can't think of any reason that would be useful (and it kinda defeats the whole point of having package lexicals, anyway) except as an insane way of (not) avoiding the `use vars` syntax. :-) `use strict; my $family; my @jewels; use base qw(Exporter); use vars qw(@EXPORT @EXPORT_LEXICALS); @EXPORT = qw( foo bar $blah ); @EXPORT_LEXICALS = ( \$family, \@jewels );` [download] Man, that's just sick. ;-p bbfu Seasons don't fear The Reaper. Nor do the wind, the sun, and the rain. We can be like they are.	[reply] [d/l] [select]