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From: mogul@Su-Coyote.ARPA
Newsgroups: net.unix-wizards
Subject: Pascal doesn't like mixed-case keywords
Message-ID: <12064@sri-arpa.UUCP>
Date: Fri, 6-Apr-84 21:58:25 EST
Article-I.D.: sri-arpa.12064
Posted: Fri Apr  6 21:58:25 1984
Date-Received: Tue, 10-Apr-84 07:37:16 EST
Lines: 97

From:  Jeff Mogul <mogul@Su-Coyote.ARPA>

Description:
	Unless run in "standard" (-s) mode, the Berkeley Pascal
	language processors (pi, pc, pxp) demand lower-case-only
	keywords.  In standard mode, case in the source files is
	ignored.  This leads to a dilemma for people trying to
	compile code written originally for other compilers, since
	if they want to use any extensions, they cannot use standard
	mode.
Repeat-By:
	Try running this program through pi, pc, or pxp (don't use -s):

	PROGRAM Test(output);
	BEGIN
		writeln('hello')
	END.

Fix:
	Since this is, in effect, a change to the Berkeley Pascal
	language, you might want to think twice about installing
	it; someone you know might have been stupid enough to write
	a Pascal program with identifiers that look like keywords,
	except for case.
	
	Otherwise, this fix makes sense: it converts a private
	copy of each token to lower case when looking up keywords.

	Line numbers are for comparison only; your actual line
	numbers may vary.

	*** hash.c.old	Mon Jan 10 10:32:53 1983
	--- hash.c	Fri Apr  6 16:32:11 1984
	***************
	*** 117,122
		int *sym;
		struct ht *htp;
		int sh;

		/*
		 * The hash function is a modular hash of

	--- 124,131 -----
		int *sym;
		struct ht *htp;
		int sh;
	+ 	static char lc_buf[sizeof(token)];	/* for lower-case-ifying */
	+ 	register char *lc_bp = lc_buf;

		/*
		 * The hash function is a modular hash of
	***************
	*** 128,135
		if (cp == NIL)
			cp = token;	/* default symbol to be hashed */
		i = 0;
	! 	while (*cp)
	! 		i = i*2 + *cp++;
		sh = (i&077777) % HASHINC;
		cp = s;
		if (cp == NIL)

	--- 137,149 -----
		if (cp == NIL)
			cp = token;	/* default symbol to be hashed */
		i = 0;
	! 	while (*cp) {
	! 		register int c_tmp = *cp++;
	! 		if (isupper(c_tmp))	/* all keywords are lower-case */
	! 			c_tmp = tolower(c_tmp);
	! 		*lc_bp++ = c_tmp;	/* construct a lower-case copy */
	! 		i = i*2 + c_tmp;
	! 	}
		sh = (i&077777) % HASHINC;
		*lc_bp = 0;
		cp = lc_buf;
	***************
	*** 131,139
		while (*cp)
			i = i*2 + *cp++;
		sh = (i&077777) % HASHINC;
	! 	cp = s;
	! 	if (cp == NIL)
	! 		cp = token;
		/*
		 * There are as many as MAXHASH active
		 * hash tables at any given point in time.

	--- 145,152 -----
			i = i*2 + c_tmp;
		}
		sh = (i&077777) % HASHINC;
	! 	*lc_bp = 0;
	! 	cp = lc_buf;
		/*
		 * There are as many as MAXHASH active
		 * hash tables at any given point in time.