Ralf Mattes <r...@seid-online.de> writes: > On Thu, Aug 24, 2017 at 10:29:41AM +0200, Arne Babenhauserheide wrote: >> Hi Christopher, >> >> You can use GOOPS to make them generic: >> >> > (import (oop goops)) >> > (< "a" "b") > > That's not what David suggested.
No, it is not. I wrote my reply before I saw his. >> <unnamed port>:3:0: <unnamed port>:3:0: In procedure <: Wrong type argument >> in position 1: "a" >> >> Entering a new prompt. Type `,bt' for a backtrace or `,q' to continue. >> [1]> (define-method (< (a <string>) (b <string>)) (string<? a b)) >> [1]> (< "a" "b") >> $1 = #t >> >> For some functions you might need to call (define-generic <function>) >> before this (you’ll notice because define-method will signal an error). > > Is that still the case? Yes. Try: > (import (oop goops)) > (define-method (list (a <string>))) ERROR: In procedure scm-error: ERROR: #<procedure list _> is not a valid generic function Best wishes, Arne -- Unpolitisch sein heißt politisch sein ohne es zu merken
signature.asc
Description: PGP signature