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A comment on A Year in Clojure. Parent comment

Re:A Year in Clojure by disconcision on Sunday October 07, 2018 @02:11PM (#18161862)
To add on, Racket in particular has some very slick syntax for writing these kinds of things:

  (define-syntax-rule
    (let ([id expr] ...) body ...)
    ((λ (id ...) body ...) expr ...))
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Re:A Year in Clojure by yomly on Sunday October 07, 2018 @07:41PM (#18163226)
I definitely liked this about Racket but I did also find the elipses to be a bit magic to begin with...
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Re:A Year in Clojure by disconcision on Sunday October 07, 2018 @07:57PM (#18163285)
As with all things, the trick to chase the magic away is to implement them. I recently made a little term rewriting library using racket/match syntax but with the pattern/templates specifiable at runtime. Ellipses were a bit confusing to begin with but when you break list patterns down into cons pairs + a cons-like pattern binary combinator to represent ellipses, it started making sense. The unexpected thing for me was that I thought nested ellipses were going to be the tough part, but it turns out they actually just... work.
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