Re^3: Using Exporter module

Exporting doesn't mean what you think it does, at least not in Perl. To export is to remove the requirement to use a fully qualified name.

What you really want, it seems, is to make a function uncallable from outside of {something}. (A namespace? Code that originated from a certain file?) Perl doesn't provide any direct means of doing that. Perl considers this a documentation issue. If a user of your module disreguards your documentation and call a function he shouldn't, it's his own foot he's shooting.

Many programmers prepend an underscore (_) to the name of their private subs/methods as an indication that they shouldn't be called.

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Re^4: Using Exporter module by Joost (Canon) on Jul 18, 2007 at 22:45 UTC
In general, you're right. But... It is possible to make subroutines un-callable from a scope, it just makes the code uglier :-) `package Whatever; { # anything outside this scope can't call this: my $private1 = sub { print "hello"; }; # everybody can call Whatever::foo sub foo { $private1->(); # call private method print " world\n"; } } foo();` [download] "What should it profit a man, if he should win a flame war, yet lose his cool?"	[reply] [d/l]
Re^5: Using Exporter module by ikegami (Patriarch) on Jul 19, 2007 at 14:32 UTC
Another way would be to check `caller`. I didn't say it was impossible, just that Perl didn't support it. Your way requires rewritting all the calls to the function. Using `caller` requires knowing the name of all the functions that will call each private function. That's ugly, fragile and best avoided. In fact, I judged best not even mentioning them. By the way, both ways can be circumvented (with difficulty).	[reply] [d/l] [select]
Re^4: Using Exporter module by perlCrazy (Monk) on Jul 19, 2007 at 12:42 UTC
I think we can acheive this by creating private method. and not call like $self->_method() Inside module if we call the private method like this: _method($self,arguments.) and if we try to call this subroutine outside then this will thorw an error.	[reply]