Re: How to "signal" (or "require") that a certain Scheme implementation provides a certain SRFI Ciprian Dorin Craciun 28 Mar 2018 19:05 UTC
On Wed, Mar 28, 2018 at 8:34 PM, John Cowan <firstname.lastname@example.org> wrote: >> Wait, I was wrong. The canonical way should be >> (cond-expand (srfi-N)) > > > SRFI 0 cond-expand doesn't assume the same set of primitive features as R7RS > cond-expand. In particular, (library (srfi N)) is the right way on R7RS. :) My point on allowing a simple `(import (srfi 62))` and be done with it... On Wed, Mar 28, 2018 at 8:13 PM, Shiro Kawai <email@example.com> wrote: > Note that cond-expand throws an error if the feature requirement is not > satisfied, so if you don't need to customize the error message, > (cond-expand ((library (srfi N)))) should suffice the purpose. It seems that just a simple `(cond-expand ((library (srfi 62))))` doesn't throw any error at least in Chibi (it just expands into `#t`). (In Gauche it does give an error.) Therefore the only "portable" (as in "sure") way is to explicitly check for `not condition` and throw an error. :) Ciprian.