D'oh! My fault; the anonymous sub block needs to be delimited with a semicolon. Code changed.

Here's a minimal example of what I think you're looking for:

#! /usr/bin/perl -w

use strict;

sub foo
{
    print "in foo\n";

    my $bar = sub {
        print "in bar\n";
    };

    if(0 == @_) {
        $bar->();
    } else {
        for (@_) {
            print "foo called with $_; ";
            $bar->();
        }
    }
}

&foo();
&foo(qw(one two three));
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