---------- Forwarded message --------- From: Damien Mattei <damien.mat...@gmail.com> Date: Mon, Aug 29, 2022 at 12:09 PM Subject: Re: expression and definition context in Scheme To: Maxime Devos <maximede...@telenet.be>
yes , the same with 'while too, i will make it in my Scheme+ to allow inner 'define in those blocks without other stuff (in Scheme+ i had already a simple macro : (& ev ...) = (let () ev ...) that replace 'begin when 'define is needed in blocks. regards, Damien On Sun, Aug 28, 2022 at 11:30 AM Maxime Devos <maximede...@telenet.be> wrote: > On 28-08-2022 08:40, Damien Mattei wrote: > > in fact my thought was not clear, perhaps just allow a 'define in an > instructions as 'when in my example , 'define-ed variable would then be > local one in the block of 'when, will it change something in scheme > implementation in a bad way? > > Are you asking for 'when' to implicitly wrap its body in a (let () ...)? > > If so, that's trivial to implement, without changing the Scheme > implementation: > > (define-syntax-rule (when cond exp ...) > (if cond > (let () exp ...))) > > Greetings, > Maxime. >
