[r6rs-discuss] [Formal] Scheme should not be changed to be case sensitive.

From: Arthur A. Gleckler <arthur>
Date: Thu Nov 16 00:02:07 2006

On Nov 14, 2006, at 2:52 PM, Arthur A. Gleckler wrote:

> If I think of a solution, I'll pipe up. But I may have to concede
> defeat on this one.

A friend who would also prefer not to see Scheme change incompatibly
with respect to case sensitivity sent me private email about this.
The solution is obvious. The draft already includes CHAR-FOLDCASE,
so implementations will already have to know how to do case folding
according to established Unicode rules. So symbols can trivially be
case-folded as they are read -- unless, of course, the programmer
deliberately chooses to use an interning procedure that doesn't fold
case.

So R6RS is effectively already demanding that we have this support,
but demanding that it not be used for symbols, which were previously
case insensitive. It is an unnecessary incompatibility.

If we change the case sensitivity of the language, users will have to
look carefully at every identifier and every use of string->symbol to
port a program to an R6RS implementation. That is onerous and
unnecessary. And the long history of the language working the way it
does should count for something in simple decision like this.
Received on Thu Nov 16 2006 - 00:01:45 UTC