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tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts(4,5): error TS2564: Property 'a' has no initializer and is not definitely assigned in the constructor.
tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts(6,5): error TS2564: Property 'c' has no initializer and is not definitely assigned in the constructor.
tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts(8,5): error TS2564: Property '#f' has no initializer and is not definitely assigned in the constructor.
tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts(10,5): error TS2564: Property '#h' has no initializer and is not definitely assigned in the constructor.
tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts(62,5): error TS2564: Property 'a' has no initializer and is not definitely assigned in the constructor.
tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts(63,5): error TS2564: Property '#b' has no initializer and is not definitely assigned in the constructor.
tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts(90,5): error TS2564: Property 'a' has no initializer and is not definitely assigned in the constructor.
tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts(113,22): error TS2565: Property 'a' is used before being assigned.
tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts(114,23): error TS2565: Property 'b' is used before being assigned.
tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts(115,23): error TS2565: Property '#d' is used before being assigned.
==== tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts (10 errors) ====
// Properties with non-undefined types require initialization
class C1 {
a: number; // Error
~
!!! error TS2564: Property 'a' has no initializer and is not definitely assigned in the constructor.
b: number | undefined;
c: number | null; // Error
~
!!! error TS2564: Property 'c' has no initializer and is not definitely assigned in the constructor.
d?: number;
#f: number; //Error
~~
!!! error TS2564: Property '#f' has no initializer and is not definitely assigned in the constructor.
#g: number | undefined;
#h: number | null; //Error
~~
!!! error TS2564: Property '#h' has no initializer and is not definitely assigned in the constructor.
#i?: number;
}
// No strict initialization checks in ambient contexts
declare class C2 {
a: number;
b: number | undefined;
c: number | null;
d?: number;
#f: number;
#g: number | undefined;
#h: number | null;
#i?: number;
}
// No strict initialization checks for static members
class C3 {
static a: number;
static b: number | undefined;
static c: number | null;
static d?: number;
}
// Initializer satisfies strict initialization check
class C4 {
a = 0;
b: number = 0;
c: string = "abc";
#d = 0
#e: number = 0
#f: string= "abc"
}
// Assignment in constructor satisfies strict initialization check
class C5 {
a: number;
#b: number;
constructor() {
this.a = 0;
this.#b = 0;
}
}
// All code paths must contain assignment
class C6 {
a: number; // Error
~
!!! error TS2564: Property 'a' has no initializer and is not definitely assigned in the constructor.
#b: number
~~
!!! error TS2564: Property '#b' has no initializer and is not definitely assigned in the constructor.
constructor(cond: boolean) {
if (cond) {
return;
}
this.a = 0;
this.#b = 0;
}
}
class C7 {
a: number;
#b: number;
constructor(cond: boolean) {
if (cond) {
this.a = 1;
this.#b = 1;
return;
}
this.a = 0;
this.#b = 1;
}
}
// Properties with string literal names aren't checked
class C8 {
a: number; // Error
~
!!! error TS2564: Property 'a' has no initializer and is not definitely assigned in the constructor.
"b": number;
0: number;
}
// No strict initialization checks for abstract members
abstract class C9 {
abstract a: number;
abstract b: number | undefined;
abstract c: number | null;
abstract d?: number;
}
// Properties with non-undefined types must be assigned before they can be accessed
// within their constructor
class C10 {
a: number;
b: number;
c?: number;
#d: number;
constructor() {
let x = this.a; // Error
~
!!! error TS2565: Property 'a' is used before being assigned.
this.a = this.b; // Error
~
!!! error TS2565: Property 'b' is used before being assigned.
this.b = this.#d //Error
~~
!!! error TS2565: Property '#d' is used before being assigned.
this.b = x;
this.#d = x;
let y = this.c;
}
}
// Property is considered initialized by type any even though value could be undefined
declare function someValue(): any;
class C11 {
a: number;
#b: number;
constructor() {
this.a = someValue();
this.#b = someValue();
}
}
const a = 'a';
const b = Symbol();
class C12 {
[a]: number;
[b]: number;
['c']: number;
constructor() {
this[a] = 1;
this[b] = 1;
this['c'] = 1;
}
}
enum E {
A = "A",
B = "B"
}
class C13 {
[E.A]: number;
constructor() {
this[E.A] = 1;
}
}
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