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On 03/20/2013 11:34 PM, Per Bothner wrote:
The idea is that you could implement $construct$:cname thus:
(define-syntax $construct$:cname
(syntax-rules ()
((_ . args) (construct-from-string cname-maker . args))))
This assumes you also a function cname-maker.
Then:
&cname{abc&(+ 3 4)z} ==> (cname-maker "abc7z")
&cname[id: "n7"]{&(+ 3 4)abc} ==> (cname-maker id: "n7" "7abc")
I came up with something that I think is better than construct-from-string: A new syntax: (define-simple-constructor cname cname-maker [str-maker]) This binds $construct$:cname such that: ($construct$:cname [init-arg ... $>>$] text-arg ...) is mapped to: (cname-maker init-arg ... (str-maker text-arg ...)) cname-maker and str-maker are user-supplied macros or functions. I.e. either names of syntax or expression that evaluate to functions. str-maker defaults to $string$ -- --Per Bothner per@xxxxxxxxxxx http://per.bothner.com/