Re^2: How to pass an argument to a Module?

I still didn't manage to do it with Perl6::Export::Attrs (i'll try more - help appreciated - details at the end of this message).
But finally i managed to override the import() methods appropriately for the cases when Export is used. Simply overriding import() didn't work, as i lost the benefit of Export. I had to use the export_to_level() method (defined by Export) in the overriden import().
Here is the simple sample code (all files start with use strict and warnings).

package Mod2;

require Exporter;
our @ISA = qw(Exporter);
our @EXPORT = qw(subr); # Exported by default

sub import { 
    print "import() was called with arguments : @_\n"; 

    my $my_arg = pop @_;
        # i have to pop(), 
        # because export_to_level() doesn't want to see $my_arg
    print "my arg: $my_arg\n";

    Mod2->export_to_level(1, @_);
}

sub subr { return "subr() was called\n"; }
1;
[download]

And the script to run it :

use Mod2 'argument'; 
print subr();
[download]

Which displays :

import() was called with arguments : Mod2 argument
my arg: argument
subr() was called
[download]

It works !

Now with Perl6::Export::Attrs, i tried this (with the same script, using Mod3 instead of Mod2; i also tried to not put any argument after use Mod3;) :

package Mod3;

use Perl6::Export::Attrs;

sub subr :Export(:DEFAULT) { return "subr() was called\n"; }

IMPORT{ print "inside the IMPORT block\n"; }

1;
[download]

and obtained this output:

inside the IMPORT block
Can't call method "IMPORT" without a package or object reference at Mo
+d3.pm line 11.
Compilation failed in require at Script3.pl line 5.
BEGIN failed--compilation aborted at Script3.pl line 5.
[download]

Does anyone know how to use this IMPORT block properly?

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Re^3: How to pass an argument to a Module? by Anonymous Monk on Sep 09, 2012 at 17:00 UTC
Does anyone know how to use this IMPORT block properly? Presumably the author. Seeing how the module never tests this IMPORT block business (Perl6-Export-Attrs-0.0.3/t/00.load.t), I would complain to the author. You can probably get away with writing `sub IMPORT {}`, cause that works for BEGIN/END/... also	[reply] [d/l]
Re^4: How to pass an argument to a Module? by mascip (Pilgrim) on Sep 09, 2012 at 18:25 UTC
The author's response (i tried it and it works, with sub IMPORT) : This is not a bug in the module. The problem is that you specified: `sub subr :Export(:DEFAULT) { return "subr() was called\n"; }` [download] :DEFAULT exports are only exported when the module is use'd with no arguments at all. But then you call: `use Mod3 'argument';` [download] with an argument, so the :DEFAULT exports don't happen. You could fix this by specifying: `sub subr :Export(:MANDATORY) { return "subr() was called\n"; }` [download] (assuming you always want subr() exported). If not, then you need to specifically request subr(), like this: `use Mod3 '&subr', 'argument';` [download] or request all the defaults, like this: `use Mod3 ':DEFAULT', 'argument';` [download]	[reply] [d/l] [select]
Re^4: How to pass an argument to a Module? by mascip (Pilgrim) on Sep 09, 2012 at 17:05 UTC
`IMPORT{ print "inside the IMPORT block, with arguments @_\n"; }` [download] works but does the same thing as when i override import() : my subroutines are not exported to the symbol table. I'll write to the author.	[reply] [d/l]
Re^3: How to pass an argument to a Module? by Anonymous Monk on Sep 09, 2012 at 17:03 UTC
`$ perl -MO=Deparse,-p -e " IMPORT { warn(666); } " do { warn(666) }->IMPORT; -e syntax OK $ perl -MO=Deparse,-p -e " sub IMPORT { warn(666); } " sub IMPORT { warn(666); } -e syntax OK` [download]	[reply] [d/l]