git.iko.soy/elk
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elk/libraries/Native/JavaScript.js
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2Elm.Native.JavaScript = function(elm) {
3 'use strict';
5 elm.Native = elm.Native || {};
6 if (elm.Native.JavaScript) return elm.Native.JavaScript;
8 var List = Elm.Native.List(elm);
10 function fromJS(v) {
11 var type = typeof v;
12 if (type === 'number' ) return v;
13 if (type === 'boolean') return v;
14 if (type === 'string' ) return List.fromArray(v);
15 if (v instanceof Array) {
16 var arr = [];
17 var len = v.length;
18 for (var i = 0; i < len; ++i) {
19 var x = fromJS(v[i]);
20 if (x !== null) arr.push(x);
21 }
22 return List.fromArray(arr);
23 }
24 if (type === 'object') {
25 var rec = { _:{} };
26 for (var f in v) {
27 var x = fromJS(v[f]);
28 if (x !== null) rec[f] = x;
29 }
30 return rec;
31 }
32 return null;
33 }
35 function toJS(v) {
36 var type = typeof v;
37 if (type === 'number' || type === 'boolean') return v;
38 if (type === 'object' && '_' in v) {
39 var obj = {};
40 for (var k in v) {
41 var x = v[k];
42 if (x !== null) obj[k] = x;
43 }
44 return obj;
45 }
46 if (type === 'object' && (v.ctor === 'Cons' || v.ctor === 'Nil')) {
47 var array = List.toArray(v);
48 for (var i = array.length; i--; ) {
49 array[i] = toJS(array[i]);
50 }
51 if (typeof array[0] === 'string') array.join('');
52 return array;
53 }
54 return null;
55 }
57 function fromRecord(r) {
58 if (typeof r === 'object' && '_' in r) {
59 return toJS(r);
60 }
61 throw new Error("'fromRecord' must be called on a record.");
62 }
64 function id(n) { return n }
66 return elm.Native.JavaScript = {
67 toFloat : id,
68 toBool : id,
69 toInt : function(n) { return n|0 },
70 toString : function(s) { return List.fromArray(s) },
71 toList : List.fromArray,
72 fromString : function(s) { return List.toArray(s).join('') },
73 fromList : List.toArray,
74 fromInt : id,
75 fromFloat : id,
76 fromBool : id,
77 toRecord : fromJS,
78 fromRecord : fromRecord
79 };
81};