blob: 2dbd078e3d951d0c87721bfe751cf3500d341af4 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
|
(.module:
[library
[lux #*
[control
["." function]]]]
[//
["." equivalence (#+ Equivalence)]
[functor
["." contravariant]]])
(interface: .public (Order a)
{#.doc "A signature for types that possess some sense of ordering among their elements."}
(: (Equivalence a)
&equivalence)
(: (-> a a Bit)
<)
)
(type: .public (Comparison a)
{#.doc (doc "An arbitrary comparison between two values, with the knowledge of how to order them.")}
(-> (Order a) a a Bit))
(def: .public (<= order parameter subject)
{#.doc (doc "Less than or equal.")}
Comparison
(or (\ order < parameter subject)
(\ order = parameter subject)))
(def: .public (> order parameter subject)
{#.doc (doc "Greater than.")}
Comparison
(\ order < subject parameter))
(def: .public (>= order parameter subject)
{#.doc (doc "Greater than or equal.")}
Comparison
(or (\ order < subject parameter)
(\ order = subject parameter)))
(type: .public (Choice a)
{#.doc (doc "A choice comparison between two values, with the knowledge of how to order them.")}
(-> (Order a) a a a))
(def: .public (min order x y)
{#.doc (doc "Minimum.")}
Choice
(if (\ order < y x) x y))
(def: .public (max order x y)
{#.doc (doc "Maximum.")}
Choice
(if (\ order < y x) y x))
(implementation: .public functor
(contravariant.Functor Order)
(def: (map f order)
(implementation
(def: &equivalence
(\ equivalence.functor map f (\ order &equivalence)))
(def: (< reference sample)
(\ order < (f reference) (f sample))))))
|