Depending on your requirement for this functionality, you could use eval and call your module at run-time only with the scope of this function. eg.

my $func = eval {
    use MyFunction;
    return MyFunction->method();
};
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The problem with this approach however, is that your module usage will only have a limited scope. Although, depending upon your script design, this could also offer some advantages.

perl -e 's&&rob@cowsnet.com.au&&&split/[@.]/&&s&.com.&_&&&print'

It's an IRC bot and each of the modules extend it's functionality in some way, so it becomes a pain having to restart the thing just to test minor changes.

You don't want to use eval(BLOCK) though. The block is compiled at the surrounding's compile-time. You want eval(EXPR).

Compare this:

#!/usr/bin/perl -l
print 'pre';
eval { BEGIN { print 'compiling eval block' } };
print 'post';
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with this:

#!/usr/bin/perl -l
print 'pre';
eval q{ BEGIN { print 'compiling eval expr' } };
print 'post';
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package QStat;

BEGIN {
    print "Compiling QStat!\n";
}

sub foo {}

1;
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Compiling QStat!
Compiling QStat!
Subroutine foo redefined at QStat.pm line 7.
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Yes it does that for me too but when I change something in one of the modules and then make it reload the changes in whatever sub I've changed don't seem to show through.

This is interesting!

If you're importing subs, you must also replace them in the importing package. It's best to call import() on the reloaded package specifically. Observe:

use QStat;
foo();
print "QStat foo is: ", \&QStat::foo, "\n";
print "Imported foo is: ", \&main::foo, "\n";

<STDIN>;

my $loc = $INC{QStat};
delete $INC{QStat};
require $loc;

# slightly more difficult
# QStat->import();

print "After import, foo is: ", \&main::foo, "\n";
print "And in the package it is: ", \&QStat::foo, "\n";
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Try it with and without the import(), and you'll see what's going on. *foo in the main package and *foo in QStat will point to different CVs, and that's the problem. (The STDIN part is in there so I could change what foo() does while the program is running.)

I wonder if it would be worth writing a 'reimport' module...

--
Ilya Martynov (http://martynov.org/)

/\/\averick
perl -l -e "eval pack('h*','072796e6470272f2c5f2c5166756279636b672');"