You're familiar with the use bytes pragma, right? Without it, perl operates with unicode characters, as in 
        # prints '1'
    print length("\x{03c5}"), "\n";

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while with use bytes, it falls back to byte semantics: 
        # prints '2'
    use bytes;
    print length("\x{03c5}"), "\n";

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Now what if I have a module Foo.pm that does a simple calculation: 
package Foo;

sub len {
    return length("\x{03c5}");
}

1;

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and I want to impose use bytes semantics on it without modifying its code? Things like 
BEGIN {
    package Foo;
    use bytes;
}
use Foo;

package main;
print Foo::len(), "\n";

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won't work because use bytes modifies the behaviour in its lexical scope. Ideas, anyone?

In reply to impose 'use bytes' on another package by saintmike

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