1
0
mirror of https://github.com/janet-lang/janet synced 2024-12-23 23:10:26 +00:00

Merge pull request #2 from Gavlooth/master

 Add examples
This commit is contained in:
Calvin Rose 2018-03-20 10:55:26 -04:00 committed by GitHub
commit c977c339a2
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23

56
examples/utils.dst Normal file
View File

@ -0,0 +1,56 @@
(defn- reverse-array [t]
(var n (dec (length t)) )
(var reversed [])
(while (>= n 0)
(array-push reversed (get t n))
(-- n))
reversed)
(defn- reverse-tuple [t]
(def max (length t))
(var n 0)
(var reversed (tuple))
(while (< n max )
(:= reversed (tuple-prepend reversed (get t n)))
(++ n))
reversed)
(defn reverse [t]
(def the-type (type t))
(cond (= the-type :tuple) (reverse-tuple t)
(= the-type :array) (reverse-array t)))
(defmacro if-not
"Sorthand for (if (not ... "
[condition exp-1 exp-2]
(tuple 'if (tuple 'not condition)
exp-1
exp-2))
(defn comp0-
"Compose two functions. Second function must accept only one argument)"
[f g] (fn [x] (f (g x))))
(defn comp
"Takes multiple functions and returns a function that is the composition
of those functions. Resulting function accepts a variable number of
arguments"
[& functions]
(def len (length functions))
(if (zero? len)
nil
(if (one? len)
(do
(def the-composition (get functions 0))
(fn [& x]
(apply the-composition x)))
(do
(def f (get functions 0))
(def g (get functions 1))
(apply comp (comp0 f g) (array-slice functions 2 -1))) )))