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From: gateley@m2.csc.ti.com (John Gateley)
Newsgroups: comp.lang.scheme
Subject: Re: Semantic domains
Message-ID: <122192@ti-csl.csc.ti.com>
Date: 3 May 90 19:32:31 GMT
References: <1862@geocub.greco-prog.fr>
Sender: news@ti-csl.csc.ti.com
Organization: TI Computer Science Center, Dallas
Lines: 16

In article <1862@geocub.greco-prog.fr> casteran@geocub.greco-prog.fr (Pierre Casteran) writes:
>in the draft standard for Scheme, the domain equation for pairs is
>Ep = L x L x T
>I understand that a pair is a couple of locations, but not the role played
>by the boolean composant.

The boolean component is used for read only data:
I cannot find the section of the semantics which
constructs data (it may have been omitted), but
any data created by quote can be considered read-only, and
is not modifiable by any mutation procedures.

Check out the definition of set-car in the semantics.

John
gateley@m2.csc.ti.com