sub a {
   sub x { print "I came from a\n"; }
}

sub b {
   sub x { print "I came from b\n"; }
}

x();
a(); x();
b(); x();

##</code><code>##

I came from b
I came from b
I came from b

##</code><code>##

sub a {
    local(*x) = sub { "from a" };
    doit();
}

sub b {
    local(*x) = sub { "from b" };
    doit();
}

sub doit {
    print "I came ", x(), "\n";
}