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-rw-r--r--com/simatime/core.scm73
1 files changed, 73 insertions, 0 deletions
diff --git a/com/simatime/core.scm b/com/simatime/core.scm
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+++ b/com/simatime/core.scm
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+(define-module (com simatime core))
+
+;;
+;; old core, do i still need this?
+;;
+
+(define (not x) (if x #f #t))
+(define (null? obj) (if (eqv? obj '()) #t #f))
+(define (list objs) objs)
+(define (identity obj) obj)
+(define (flip f) (lambda (x y) (f y x)))
+(define (curry f a) (lambda (b) (apply f (cons a (list b)))))
+(define (compose f g) (lambda (x) (f (apply g x))))
+(define zero? (curry = 0))
+(define positive? (curry < 0))
+(define negative? (curry > 0))
+(define (odd? n) (= (mod n 2) 1))
+(define (even? n) (= (mod n 2) 0))
+
+(define (foldr f end lst)
+ (if (null? lst)
+ end
+ (f (car lst) (foldr f end (cdr lst)))))
+
+(define (foldl f acc lst)
+ (if (null? lst)
+ acc
+ (foldl f (f acc (car lst)) (cdr lst))))
+
+(define fold foldl)
+
+(define (unfold f init pred)
+ (if (pred init)
+ (cons init '())
+ (cons init (unfold f (f init) pred))))
+
+(define (mem* pred op)
+ (lambda (acc next)
+ (if (and (not acc) (pred (op next)))
+ next
+ acc)))
+
+(define (sum lst) (fold + 0 lst))
+(define (produce lst) (fold * 0 1 lst))
+
+(define (max nums)
+ (fold (lambda (x y) (if (> x y) x y))
+ (car nums) (cdr nums)))
+
+(define (min nums)
+ (fold (lambda (x y) (if (< x y) x y))
+ (car nums) (cdr nums)))
+
+(define (length lst) (fold (lambda (x y) (+ x 1)) 0 lst))
+(define (reverse lst) (fold (flip cons) '() lst))
+(define (memq obj lst) (fold (mem* (curry eq? obj) identity) #f lst))
+(define (memv obj lst) (fold (mem* (curry eqv? obj) identity) #f lst))
+(define (member obj lst) (fold (mem* (curry equal? obj) identity) #f lst))
+(define (assq obj alist) (fold (mem* (curry eq? obj) car) #f alist))
+(define (assv obj alist) (fold (mem* (curry eqv? obj) car) #f alist))
+(define (assoc obj alist) (fold (mem* (curry equal? obj) car) #f alist))
+(define (map f lst) (foldr (lambda (x y) (cons (f x) y)) '() lst))
+(define (filter pred lst) (foldr (lambda (x y) (if (pred x) (cons x y) y)) '() lst))
+
+
+;;
+;; clojure-like stuff
+;;
+
+(define (pr . a)
+ (for-each display args))
+
+(define (prn . a) (apply pr a) (newline))