Subject: bug#61660: [feature request] optimization of case-lambda

From: Ludovic Courtès <[email-masked]>
Date: Mon, 27 Feb 2023 11:11:29 +0100

Hi Daniel,

lloda <[email-masked]> skribis:

> From 61ed612fb36108e395bdee4b1bbb46b49ef017b3 Mon Sep 17 00:00:00 2001
> From: Daniel Llorens <[email-masked]>
> Date: Thu, 23 Feb 2023 17:38:10 +0100
> Subject: [PATCH] peval reduces some inlined case-lambda calls
>
> * module/language/tree-il/peval.scm (peval): Reduce multiple case lambda
>   in <call> trees according to the number of arguments. Do not try to
>   reduce case-lambda using keyword arguments.
> * test-suite/tests/peval.test: Tests.

[...]

> +++ b/module/language/tree-il/peval.scm
> @@ -1668,6 +1668,29 @@ top-level bindings from ENV and return the resulting expression."
>  
>                    (log 'inline-end result exp)
>                    result)))))
> +           (($ <lambda> src-proc meta orig-body)
> +            ;; If there are multiple cases and one matches nargs, omit all the others.
> +            (or (and
> +                 (lambda-case-alternate orig-body)
> +                 (let ((nargs (length orig-args)))
> +                   (let loop ((body orig-body))
> +                     (match body
> +                       (#f #f) ;; No matching case; an error.
> +                       (($ <lambda-case> src-case req opt rest kw inits gensyms case-body alt)
> +                        (cond (kw
> +                               ;; FIXME: Not handling keyword cases.
> +                               #f)

Maybe s/FIXME/XXX/ since it’s at most a limitation, certainly not a bug.

It LGTM and Andy already approved it on IRC, so go ahead!

Ludo’.