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From: arnold@emory.uucp (Arnold D. Robbins {EUCC})
Newsgroups: comp.lang.c
Subject: Re: *\"LDA\" ok?
Message-ID: <2211@emory.uucp>
Date: Wed, 26-Aug-87 13:34:00 EDT
Article-I.D.: emory.2211
Posted: Wed Aug 26 13:34:00 1987
Date-Received: Fri, 28-Aug-87 06:20:06 EDT
References: <8877@brl-adm.ARPA> <8088@mimsy.UUCP> <87@splut.UUCP>
Reply-To: arnold@emory.UUCP (Arnold D. Robbins {EUCC})
Organization: Emory University Computing Center
Lines: 43

There has been considerable discussion about C's strings and the fact that
the lack of string operands is a hindrance. Several years ago I suggested
a string operator, but I got little response. Here's my idea again.

Add a new symbol for use in comparison, assignment, and argument declarations
and functions calls that pass arrays *by value*, say "`". It would be
used analogously to * in pointer declarations/use.

Array comparison:
	if (`x == `y)
	if (`x == `"LDA")

Function declaration:
	int foo (char `arg);	/* requires dope vector */
	x = foo (`x);
	char (`junk[5])();	/* function returning array! (length 5) */

Array assignment:
	`x = `y;

	There would have to be a number of new rules relating to arrays
of the same type but of different length, and using arrays of different
types. In particular, it would probably be necessary to special case
array of char so that even if two arrays are of different length, all
operations would work as if the str* functions had been called, i.e.
terminating on a 0 byte.

	The advantages of this proposal is that it adds something many
people feel has long been missing (array operations, passing arrays by
value), but without overloading an existing operator or breaking any
current code.
	The disadvantages are that function calls would now require
the use of dope vectors, and assigments and comparisons would be
compound operations (i.e. a hidden loop); so what looks like a simple,
quick operation (like comparing two integers) could be a very long,
slow operation. Function call/return times also could increase.

	Well, so much for throwing out ideas. Any comments?
-- 
Arnold Robbins
ARPA, CSNET:	arnold@emory.ARPA	BITNET: arnold@emory
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ONE-OF-THESE-DAYS:	arnold@emory.mathcs.emory.edu