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
|
=== tests/cases/conformance/expressions/typeGuards/typeGuardOfFormTypeOfEqualEqualHasNoEffect.ts ===
class C { private p: string };
>C : C
>p : string
var strOrNum: string | number;
>strOrNum : string | number
var strOrBool: string | boolean;
>strOrBool : string | boolean
var numOrBool: number | boolean
>numOrBool : number | boolean
var strOrC: string | C;
>strOrC : string | C
// typeof x == s has not effect on typeguard
if (typeof strOrNum == "string") {
>typeof strOrNum == "string" : boolean
>typeof strOrNum : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>strOrNum : string | number
>"string" : "string"
var r1 = strOrNum; // string | number
>r1 : string
>strOrNum : string
}
else {
var r1 = strOrNum; // string | number
>r1 : string
>strOrNum : number
}
if (typeof strOrBool == "boolean") {
>typeof strOrBool == "boolean" : boolean
>typeof strOrBool : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>strOrBool : string | boolean
>"boolean" : "boolean"
var r2 = strOrBool; // string | boolean
>r2 : boolean
>strOrBool : boolean
}
else {
var r2 = strOrBool; // string | boolean
>r2 : boolean
>strOrBool : string
}
if (typeof numOrBool == "number") {
>typeof numOrBool == "number" : boolean
>typeof numOrBool : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>numOrBool : number | boolean
>"number" : "number"
var r3 = numOrBool; // number | boolean
>r3 : number
>numOrBool : number
}
else {
var r3 = numOrBool; // number | boolean
>r3 : number
>numOrBool : boolean
}
if (typeof strOrC == "Object") {
>typeof strOrC == "Object" : boolean
>typeof strOrC : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>strOrC : string | C
>"Object" : "Object"
var r4 = strOrC; // string | C
>r4 : C
>strOrC : C
}
else {
var r4 = strOrC; // string | C
>r4 : C
>strOrC : string
}
|
