package foo;

sub new {
    print "I'm in foo::new()\n";
    bless {}, 'foo';
}

1;

package main;

sub foo {
    print "I'm in main::foo()\n";
}

my $o = new foo;

__output__

Bareword found where operator expected at - line 17, near "new foo"
        (Do you need to predeclare new?)
syntax error at - line 17, near "new foo"