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Date: Thu, 16 May 2013 19:15:58 +0200
From: "G.B." <rm-dash-bau-haus@dash.futureapps.de>
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Subject: Re: Seeking for papers about tagged types vs access to subprograms
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Date: 2013-05-16T19:15:59+02:00
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On 16.05.13 15:54, Dmitry A. Kazakov wrote:
>> I realize that equivalence of functions is a difficult concept in general
> There is nothing difficult in that. A function is a set of pairs. Two sets
> are equal when contain same elements.

I think the difficulty is that eq is not computable. For example,
if f1 and f2 are any Ada compilers, produce an algorithm that computes

  eq(f1, f2)

Then, proceed to finding eq of procedures computing eq.