use strict;
use warnings;
use WWW::SFDC;
use Data::Dumper;

my @names =  map {m'objects/(.*).object'} WWW::SFDC->new(
    username => ...,
    password => ...,
    url => 'https://login.salesforce.com'
)->Metadata->listMetadata({type => 'CustomObject'});

print Dumper \@names;