[r6rs-discuss] [Scheme-reports] Scheme pattern matching: the case for (case)

[Andre van Tonder]

On Wed, 22 Dec 2010, Eli Barzilay wrote:

> An hour ago, Peter Kourzanov wrote:
>> And now do:
>>
>> (define eqv? equal?)
>> (newline)
>> (write (case "asd" (("asd") #t)))
>> (newline)
>>
>> You'll find Tinyscheme, Minischeme, MIT, Scheme48/SCSH included in
>> your list. Ypsilon and Stalin exhibit this behaviour for strings,
>> but not for more structured data like vectors.
>
> This is a *very* different issue -- R5RS systems make it a core
> feature that you can change builtin functions like that, with all
> references to them changing too.

No, it doesn't.  R5RS forbids this, so the above systems are not even R5RS 
compliant.

Andre