The problem is that myuse() would be executed at run-time instead of compile-time. In which case the symbols are probably less useful. If the symbols being exported are non-code (i.e. exported variables), then use strict will have already killed the script at compile-time because the variables were not declared. Ditto for any subs that are imported that need special parsing (e.g. you want to use them without parentheses, or they have interesting prototypes). Importing is something that really needs to be done at compile-time; hence use, or at a push BEGIN.

What exactly are you hoping to achieve? If you want to combine many use Foo, use Bar, use Baz statements into a single statement, then look at Syntax::Collector and/or Import::Into. If you want to conditionally load modules, look at if. If you want to select amongst several backend modules implementing the same function, there's Module::Implementation. If you don't need to import symbols at all, and are loading modules that will e.g. be used as classes, then run-time loading is fine, and I'd recommend Module::Runtime, Class::Load, or (if you're in an experimental kind of mood) perhaps Module::Quote.

Hi tobyink,

thank you for the hints. Especially Module::Implementation could be a way to think about my problem.

Today it's done via the following:

my $code = create_use_string(%parameters);
eval "$code";
if(my $ex = $@) {
   die "Something went really wrong: $ex";
}
[download]

while create_use_string is returning a perl code snippet of the kind

use lib 'path_to_implementation_dependent_on_parameters';
use x;
use y;
[download]

You see, everything is exported. That's not nice, but it's the way the current (old) code base is relying on.

Best regards
McA

If you think you need to load+export, and you don't know how, that is strong hint (certainty) that you don't need to do this (you're doing it wrong, exporting is the devil)

Module::Load,

perl5, perl5::ingy
ToolSet
Syntax::Collector
Toolkit
rig
see perlrun#PERL5OPT , PERLLIB, PERL5LIB
sitecustomize under perlrun#* f*
how to make lexical pragma global, hints ( pl_hints $^H %^H ), taint::all, Re: batch 'use' possible? (perl5.pm Toolset.pm, Syntax::Collector , Toolkit.pm, rig.pm, sitecustomize.pl, PERL5OPT )( load multiple commonly-used favorite modules in a single import expression )

export into / Import::Into

:D

Thanks, Anonymonk! I'm going to steal this list for my talk at YAPC.

Thank you for that fast reply.

I totally agree to your statement, especially to

"[...] exporting is the devil [...]"

, but probably it can help to do a transition in an existing code base. Sometimes you have to do changes step by step.

I did find modules for the "loading" part, but not for the "exporting" to a level above the function doing the module load. Import::Into looks interesting.

Best regards
McA