On 2024-05-22 18:07, Pierpaolo Bernardi wrote:
In chez:
(cond (else (define x 7) x))
7
x
7
which looks like a bug to me. You may check if x is defined outside of
the cond expression in the other implementations which do not raise an
error too?
Sure! And the result varies a lot!
(cond (#t (define x 7) x))
(cond (else (define y 7) y))
| System | A | x | B | y |
|-------------|-------|-------|-----------|-----------|
| Bigloo | 7 | x | 7 | 7 |
| Biwa | 7 | 7 | 7 | 7 |
| Chez | error | error | 7 | 7 |
| Chibi | error | error | 7 | 7 |
| Chicken | 7 | 7 | 7 | 7 |
| Cyclone | 7 | error | 7 | error |
| Gambit | error | error | error | error |
| Gauche | 7 | 7 | 7 | 7 |
| Guile | 7 | error | 7 | error |
| Kawa | 7 | error | 7 | 7 |
| LIPS | 7 | error | error (*) | error (*) |
| Loko | error | error | error | error |
| MIT | error | error | error | error |
| Racket | 7 | error | 7 | error |
| Sagittarius | 7 | 7 | 7 | 7 |
| Scheme48 | error | error | 7 | 7 |
| Scheme 9 | error | error | 7 | 7 |
| SCM | 7 | 7 | 7 | 7 |
| STklos | 7 | 7 | 7 | 7 |
| Tinyscheme | 7 | 7 | 7 | 7 |
* LIPS does not recognise the `else` clause when it's the only
expression in `cond`.
J.
