You just broke overloading:

    # (! Scalar::Util::reftype($code) ne 'CODE') {
    if (! UNIVERSAL::isa($code, 'CODE')) {

[download]

How about:

unless (defined &$code) {

Also, isa() is a method, not a function. Using it as a function can break many things.

In reply to Re^2: on the fly methods by chromatic
in thread on the fly methods by Ojosh!ro

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