29 lines
888 B
Scheme
29 lines
888 B
Scheme
|
(define-module (game util pipe)
|
||
|
|
#:export (-> ->>)
|
||
|
|
#:version (0 1 0))
|
||
|
|
|
||
|
|
;; Thread first macro.
|
||
|
|
;; The first s-expression will be inserted as the first argument of the next s-expesssion.
|
||
|
|
;; Example: (-> 100 (/ 10) (/ 5)) becomes (/ (/ 100 10) 5)
|
||
|
|
(define-syntax ->
|
||
|
|
(syntax-rules ()
|
||
|
|
((_) #f)
|
||
|
|
((_ x) x)
|
||
|
|
((_ x (f . (f-rest ...))) (f x f-rest ...))
|
||
|
|
((_ x f) (f x))
|
||
|
|
((_ x (f . (f-rest ...)) rest ...) (-> (f x f-rest ...) rest ...))
|
||
|
|
((_ x f rest ...) (-> (f x) rest ...))
|
||
|
|
))
|
||
|
|
|
||
|
|
;; Thread last macro.
|
||
|
|
;; The first s-expression will be inserted as the last argument of the next s-expesssion.
|
||
|
|
;; Example: (-> 100 (/ 10) (/ 5)) becomes (/ 5 (/ 10 100))
|
||
|
|
(define-syntax ->>
|
||
|
|
(syntax-rules ()
|
||
|
|
((_) #f)
|
||
|
|
((_ x) x)
|
||
|
|
((_ x (f ...)) (f ... x))
|
||
|
|
((_ x f) `(f x))
|
||
|
|
((_ x (f ...) rest ...) (->> (f ... x) rest ...))
|
||
|
|
((_ x f rest ...) (->> (f x) rest ...))))
|