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From: wex@SW.MCC.COM (Alan Wexelblat)
Newsgroups: comp.lang.modula2
Subject: CONVERT, and the meaning of "meaning"
Message-ID: <8807071341.AA09718@banzai-inst.sw.mcc.com>
Date: 7 Jul 88 13:41:28 GMT
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Reply-To: Info-Modula2 Distribution List 
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Alan Lovejoy wrote:

> According to Barry Cornelius's posting on the subject, the BSI proposal
> currently on the table is "CONVERT(CARDINAL, -1)" as the syntax for a
> "meaning-preserving" conversion.  In this case the "value" is an exception.
> What an "exception" is, is formally undefined.  It is expected to be either
> a no-op, a program abort or a trap to a debugging tool.

This strikes me as a singularly *bad* idea.  What on earth do we think
"meaning" is if something "means" something undefined (in this case an
exception)?

Since the type of the function CONVERT is pretty floppy anyway, why not add
an out-of-band signal (like EOF) to denote a value outside the range of
possible conversions?

I hope we're not going the way of C which thinks it's acceptable to give "an
exception" (core dump) every time some poor programmer passes NULL to
strlen()!

--Alan Wexelblat
ARPA: WEX@MCC.COM
UUCP: {harvard, gatech, pyramid, &c.}!sally!im4u!milano!wex

"How do we measure the distance between Ken Kesey and Carlos Lehder?"
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