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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.ada
Subject: Re: How to get Ada to ?cross the chasm??
Date: Thu, 10 May 2018 12:32:19 -0700
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Date: 2018-05-10T12:32:19-07:00
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Niklas Holsti <niklas.holsti@tidorum.invalid> writes:
>> and there's an explicit reference there.
> Thanks, this explains it.

Note though that the need for the explicit reference is a consequence of
the type system, not something inherent in the concept of corecursion.
In a lazy version of Scheme you could write that list without any
explicit self-reference using the Y combinator,

    Y = λf. (λx. f (x x)) (λx. f (x x))

(Don't ask me to explain how that works, but there is a description in
Wikipedia).  It's just that the Y combinator can't be written under a
Haskell-style type system, and it allows you to implement unrestricted
recursion.