lambda-core/languages/a/arkscript/lambda-core.ark at main · kserrec/lambda-core · GitHub

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# Logic
(let _true (fun (x)
  (fun (y &x) x)))
(let _false (fun (x)
  (fun (y) y)))
(let _not (fun (b)
  ((b _false) _true)))
(let _and (fun (b1)
  (fun (b2 &b1)
    ((b1 b2) _false))))
(let _or (fun (b1)
  (fun (b2 &b1)
    ((b1 _true) b2))))

## Examples
(let read_bool (fun (b)
  (print ((b "true") "false"))))

(print "Logic
-----
True / False")
(read_bool _true)
(read_bool _false)

(print "Not")
(read_bool (_not _true))
(read_bool (_not _false))

(print "And")
(read_bool ((_and _true) _true))
(read_bool ((_and _true) _false))
(read_bool ((_and _false) _true))
(read_bool ((_and _false) _false))

(print "Or")
(read_bool ((_or _true) _true))
(read_bool ((_or _true) _false))
(read_bool ((_or _false) _true))
(read_bool ((_or _false) _false))

# Church Numerals
(let _zero (fun (f) (fun (x) x)))
(let _succ (fun (n)
  (fun (f &n)
    (fun (x &n &f)
      (f ((n f) x))))))
(let _pred (fun (n)
  (fun (f &n)
    (fun (x &n &f)
      (((n (fun (g &f) (fun (h &g &f) (h (g f))))) (fun (u &x) x)) (fun (a) a))))))
(let _one (_succ _zero))

## Examples
(let read_church (fun (n)
  (print ((n (fun (x) (+ x 1))) 0))))

(print "
Church Numerals
---------------
Zero / Succ")
(read_church _zero)
(read_church _one)
(read_church (_succ _one))
(read_church (_succ (_succ _one)))

(print "Pred")
(read_church (_pred _one))
(read_church (_pred (_succ _one)))
(read_church (_pred (_succ (_succ _one))))