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
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
|
//// [typeGuardsInFunctionAndModuleBlock.ts]
// typeguards are scoped in function/module block
function foo(x: number | string | boolean) {
return typeof x === "string"
? x
: function f() {
var b = x; // number | boolean
return typeof x === "boolean"
? x.toString() // boolean
: x.toString(); // number
} ();
}
function foo2(x: number | string | boolean) {
return typeof x === "string"
? x
: function f(a: number | boolean) {
var b = x; // new scope - number | boolean
return typeof x === "boolean"
? x.toString() // boolean
: x.toString(); // number
} (x); // x here is narrowed to number | boolean
}
function foo3(x: number | string | boolean) {
return typeof x === "string"
? x
: (() => {
var b = x; // new scope - number | boolean
return typeof x === "boolean"
? x.toString() // boolean
: x.toString(); // number
})();
}
function foo4(x: number | string | boolean) {
return typeof x === "string"
? x
: ((a: number | boolean) => {
var b = x; // new scope - number | boolean
return typeof x === "boolean"
? x.toString() // boolean
: x.toString(); // number
})(x); // x here is narrowed to number | boolean
}
// Type guards do not affect nested function declarations
function foo5(x: number | string | boolean) {
if (typeof x === "string") {
var y = x; // string;
function foo() {
var z = x; // string
}
}
}
module m {
var x: number | string | boolean;
module m2 {
var b = x; // new scope - number | boolean | string
var y: string;
if (typeof x === "string") {
y = x // string;
} else {
y = typeof x === "boolean"
? x.toString() // boolean
: x.toString(); // number
}
}
}
module m1 {
var x: number | string | boolean;
module m2.m3 {
var b = x; // new scope - number | boolean | string
var y: string;
if (typeof x === "string") {
y = x // string;
} else {
y = typeof x === "boolean"
? x.toString() // boolean
: x.toString(); // number
}
}
}
//// [typeGuardsInFunctionAndModuleBlock.js]
// typeguards are scoped in function/module block
function foo(x) {
return typeof x === "string"
? x
: function f() {
var b = x; // number | boolean
return typeof x === "boolean"
? x.toString() // boolean
: x.toString(); // number
}();
}
function foo2(x) {
return typeof x === "string"
? x
: function f(a) {
var b = x; // new scope - number | boolean
return typeof x === "boolean"
? x.toString() // boolean
: x.toString(); // number
}(x); // x here is narrowed to number | boolean
}
function foo3(x) {
return typeof x === "string"
? x
: (function () {
var b = x; // new scope - number | boolean
return typeof x === "boolean"
? x.toString() // boolean
: x.toString(); // number
})();
}
function foo4(x) {
return typeof x === "string"
? x
: (function (a) {
var b = x; // new scope - number | boolean
return typeof x === "boolean"
? x.toString() // boolean
: x.toString(); // number
})(x); // x here is narrowed to number | boolean
}
// Type guards do not affect nested function declarations
function foo5(x) {
if (typeof x === "string") {
var y = x; // string;
function foo() {
var z = x; // string
}
}
}
var m;
(function (m) {
var x;
var m2;
(function (m2) {
var b = x; // new scope - number | boolean | string
var y;
if (typeof x === "string") {
y = x; // string;
}
else {
y = typeof x === "boolean"
? x.toString() // boolean
: x.toString(); // number
}
})(m2 || (m2 = {}));
})(m || (m = {}));
var m1;
(function (m1) {
var x;
var m2;
(function (m2) {
var m3;
(function (m3) {
var b = x; // new scope - number | boolean | string
var y;
if (typeof x === "string") {
y = x; // string;
}
else {
y = typeof x === "boolean"
? x.toString() // boolean
: x.toString(); // number
}
})(m3 = m2.m3 || (m2.m3 = {}));
})(m2 || (m2 = {}));
})(m1 || (m1 = {}));
|
