() <to...@tuxteam.de> () Tue, 28 Dec 2021 08:19:04 +0100 I /think/ the ellipsis is at a wrong place there. Note that I'm coming from "traditional" match, and I just have wrapped half of my brain around that (which, BTW, is somewhat painful :-)
Haha, i know exactly how you feel.
So take this with a grain of salt.
* Phenomenology (aka: I barely know what I'm doing):
If you replace your ellipses above by ". ,rest", things seem
to work:
(define (unbogus x)
(sxml-match x
((a (@ . ,attrs) . ,rest)
`(a (@ ,@(delete '(shape "rect") attrs)) . ,rest))))
(unbogus '(a (@ (shape "rect") (href "foo.html")) "kid"))
=> (a (@ (href "foo.html")) "kid")
Cool. I guest the ". ,rest" is a shortcut for the ellipses.
* Philosophy (aka blah, blah)
If those ellipses resemble what match do, I think they are
wrong there:
(@ . ,attrs) ...
would mean zero or more times the shape "(@ . ,attrs)". I
think this isn't what you want.
Ah, right! The ellipses are a tail that need to follow a head.
I guess i was confused by the documentation's use of ellipses in
the conventional sense rather than the literal sense:
(define (album->html x)
(sxml-match x
[(album (@ (title ,t)) (catalog (num ,n) (fmt ,f)) ...)
`(ul (li ,t)
(li (b ,n) (i ,f)) ...)]))
Anyway, thanks to your help, i've managed to cobble together the
following code, attached here for the benefit of future self:
#!/usr/bin/guile -s
!#
(use-modules
(ice-9 pretty-print)
(sxml match))
(define (pp x)
(pretty-print x)
(newline))
(define (unbogus x)
(sxml-match x
((a (@ . ,attrs) . ,rest)
`(a (@ ,@(delete '(shape "rect") attrs)) . ,rest))
(,otherwise
(if (string? x)
x
`(,(car x) ,(cadr x)
,@(map unbogus (cddr x)))))))
(define one '(a (@ (shape "rect") (href "foo.html")) "kid"))
(newline)
(pp one)
(pp (unbogus one))
(define bad `(p (@) "some text and " ,one " and " ,one))
(newline)
(pp bad)
(pp (unbogus bad))
Maybe it's idiomatic. Feedback on how to improve it welcome!
--
Thien-Thi Nguyen -----------------------------------------------
(defun responsep (query) ; (2021) Software Libero
(pcase (context query) ; = Dissenso Etico
(`(technical ,ml) (correctp ml))
...)) 748E A0E8 1CB8 A748 9BFA
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