Perl function name clash

问题

I'm in a situation where a module I'm using has a function whose name is exactly the same as one in my own module. When I try to call the function in my module (OO Perl, so $self->function) it's calling the function from the other module instead.

I've already got around it by renaming my function but as a matter of interest, is there any way of explicitly calling the function from my module?

edit: this is essentially what I'm doing

package Provider::WTO;

use base qw(Provider); # Provider contains a method called date

use utilities::utils; #not my module so don't blame me for the horrendous name :-)
...
sub _get_location
{
    my $self = shift;
    return $self->date."/some_other_string"; # calls utilities::utils::date()
}

回答1:

If the name conflict is caused by an import from another module you might consider either Sub::Import, which allows for easy renaming of imports, even if the exporting module doesn't explicitly support that, or namespace::autoclean/namespace::clean.

package YourPackage;

use Sub::Import 'Some::Module' => (
    foo => { -as => 'moo' },
); # imports foo as moo

sub foo { # your own foo()
    return moo() * 2; # call Some::Module::foo() as moo()
}

The namespace cleaning modules will only be helpful if the import is shadowing any of your methods with a function, not in any other case:

package YourPackage;

use Some::Module; # imports foo
use Method::Signatures::Simple
use namespace::autoclean; # or use namespace::clean -except => 'meta';

method foo {
    return foo() * 2; # call imported thing as a function
}

method bar {
    return $self->foo; # call own foo() as a method
}

1;

This way the imported function will be removed after compiling your module, when the function calls to foo() are already bound to the import. Later, at your modules runtime, a method called foo will be installed instead. Method resolution always happens at runtime, so any method calls to ->foo will be resolved to your own method.

Alternatively, you can always call a function by it's fully-qualified name, and don't import it.

use Some::Module ();
Some::Module::foo();

This can also be done for methods, completely disabling runtime method lookup:

$obj->Some::Module::foo();

However, needing to do this is usually a sign of bad design and you should probably step back a little and explain what you did to get you into this situation in the first place.

回答2:

Do you need that subroutine from the offending module? Without knowing more about it, I think the quick fix is to explicitly not import it with an empty import list:

 use Interfering::Module ();

If you need other imported things, you can specify the ones that you need:

 use Interfering::Module qw(sub1 sub2);

If the list of exports you want is really long, you can just exclude the interfering subroutine:

 use Interfering::Module qw(!bad_sub);

If none of those work, you'll have to say more about the interfering module.

回答3:

Are you sure this is happening in a method call (i.e. $self->function) and not a regular call?

If that's the case, then the only way I can see of that happening is your module is extending the other module, and you're not defining the method in question, and the module you're extending defines a function with the same name as the method you're trying to call.

In any case, you can not import the offending function into your namespace with use Foreign::Module ().

If it's a regular function call that's getting clobbered, you can refer to it as Your::Module->function.

来源：https://stackoverflow.com/questions/3673622/perl-function-name-clash

标签

perl

function

naming