yes :-) i will keep it in mind. It is a bit like a let* i tends to forget it sometimes.
On Fri, Aug 4, 2023 at 10:31 AM Jean Abou Samra <j...@abou-samra.fr> wrote: > > Le vendredi 04 août 2023 à 10:23 +0200, Damien Mattei a écrit : > > i know what disturb me in this error, it is because the order of > definitions has effect but i always learn (was it right?) that in > scheme the order of definitions should have no effect on the resulting > evaluations. > > > > Not really, you cannot do > > (define b (1+ a)) > (define a 5) > > either. You *can* do > > (define (b) (1+ a)) > (define a 5) > > but that's because the definition of b does not use the binding for a, only > capture it in a lambda abstraction. The reason you cannot do > > (define b (mac 1)) > (define-syntax-rule (mac x) x) > > is that the (mac 1) expression used in the binding of b is using the macro > (at expand time), just like in my first example it was using the variable a > (at runtime). > > >
