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From: jeff@aiai.ed.ac.uk (Jeff Dalton)
Subject: Re: Associativity of implication (was Re: Deontic Logic. What is it?)
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Date: Mon, 20 Feb 1995 17:35:30 GMT
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In article <jgllgher.792963618@ashe> jgllgher@cs.tcd.ie (Dara Gallagher) writes:
>I've often wondered why -> associates to the left. I think it would be
>better if A -> B -> C meant A -> (B -> C) because
>1. It reflects the fact that we (most of us) read from left to right; i.e.
>   A -> B -> C can be read as asserting "assuming A, then assuming B, we
>   can conclude C"
>2. The function space constructor -> is right associative; the Curry-Howard
>   isomorphism would "look" better if implication was the same.
>
>Any thoughts?

APL is a programming language with many operators, and I think they're
all right associative (even the ordinary aritmetic ones that are
usually left-associative).  This turns out to work fairly well.

-- jd
