Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/5/84; site rexago1.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!gamma!epsilon!zeta!sabre!petrus!bellcore!decvax!cwruecmp!rexago1!rich
From: rich@rexago1.UUCP (K. Richard )
Newsgroups: net.lang.c
Subject: lambda defs in C
Message-ID: <187@rexago1.UUCP>
Date: Wed, 5-Feb-86 12:39:53 EST
Article-I.D.: rexago1.187
Posted: Wed Feb  5 12:39:53 1986
Date-Received: Fri, 7-Feb-86 20:37:06 EST
Distribution: net
Organization: Roadway Express Inc., Akron, OH
Lines: 31

I often find myself creating highly localized register variables in an
attempt to synthesize common sub expression optimization:

	{
		register  char _q = *((x.y)->z);

		if (_q == 'a' || _q == 'b' || _q == 'c') { ...

I also want to return values from arbitrary expressions like a for loop.
Lisp has something called a lambda definition which is something like
a local temporary function definition. Sort of like:

	if ( lambda int f(register char _q = *((x.y)->z)) {
			return(_q == 'a' || _q == 'b' || _q == 'c');
		}	/* end of lambda def */ ) { ...

or

	x = lambda int f() {
		for (...) {
			...
			return(some expression);
			...
		}	/* for */
	}	/* lambda */

So, academically, if we were to add a simlar feature to a new dialect of C,
or to construct a pre-preprocessor for ansii C (a la C++), what problems
do you see?

K. Richard Magill