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From: Paul Rubin <no.email@nospam.invalid>
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Subject: Re: How to get Ada to ?cross the chasm??
Date: Tue, 01 May 2018 17:02:12 -0700
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Date: 2018-05-01T17:02:12-07:00
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"Dan'l Miller" <optikos@verizon.net> writes:
> I am pretty sure that Jeffrey Carter's school of thought would be
> focusing on the “clever run-time devices to avoid excessive copying”

Haskell in fact has mutable arrays just like you're used to, but using
them safely requires treating them as something like i/o devices, so the
array state is threaded through a computation that's separated off from
the rest of your program by the type system.  It's a little bit hard to
explain.  The upshot is that it's there if you need it, but you're
better off avoiding it if you can.

Ben Lippmeier (one of the GHC developers at times) has one of the better
critiques of Haskell's array story, starting on page 17 here:

http://benl.ouroborus.net/papers/2010-impure/lippmeier-impure-world.pdf