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From: taft@adobe.com (Ed Taft)
Newsgroups: comp.lang.postscript
Subject: Re: Semantics of bind
Message-ID: <9659@adobe.UUCP>
Date: 6 Jan 91 03:06:33 GMT
References: <38.UUL1.3#5127@aladdin.com>
Sender: news@adobe.COM
Reply-To: taft@adobe.COM (Ed Taft)
Organization: Adobe Systems Incorporated, Mountain View
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In article <38.UUL1.3#5127@aladdin.com> ghost@aladdin.com (L. Peter Deutsch) writes:
>1) The Red Book seems to imply that bind will affect the top level of
>a procedure even if the procedure is read-only or execute-only, but
>not interior read- or execute-only procedures.  Is this really the
>case?

Regrettably, the red book description is misleading on this point. An array
that isn't writable will not be affected by bind, whether it is the top-level
array or a nested one.

>2) Does bind affect packed arrays?

Yes, bind affects packed arrays to arbitrary depth, in spite of the fact
that packed arrays are always read-only.

Note that for arrays, the interpreter marks nested arrays read-only as it
goes along. This is how it avoids infinite recursion if nested arrays form a
circular structure. This is not necessary for packed arrays, since it's
impossible to create a circular structure consisting entirely of packed
arrays.
Ed Taft      taft@adobe.com      ...decwrl!adobe!taft