package a::b;
use strict;
sub a::b {
    my @l = caller(0);
    open my $f, "<", $l[1];
    my $line;
    for (0..$l[2] - 1) {
        $line = <$f>;
    }
    my $pack = $l[3];
    if (!@_ && $line =~ /$pack\->/) {
        return $pack;
    } else {
        return $pack->new(@_);
    }
}
sub new {
    print "new!!! ".join(", ",@_)."\n";
}
sub c {
    print "a::b->c()!!!! ".join(", ",@_)."\n";
}
package main;
a::b;
a::b('a');
a::b->c;
a::b->c('a');