* Class fields w/esnext+[[Define]]:no shadow error With useDefineForClassFields: true and ESNext target, initializer expressions for property declarations are evaluated in the scope of the class body and are permitted to reference parameters or local variables of the constructor. This is different from classic Typescript behaviour, with useDefineForClassFields: false. There, initialisers of property declarations are evaluated in the scope of the constructor body. Note that when class fields are accepted in the ECMAScript standard, the target will become that year's ES20xx * add negative test case * Add explanatory comment
36 lines
887 B
TypeScript
36 lines
887 B
TypeScript
// @target: esnext
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// @useDefineForClassFields: true
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// With useDefineForClassFields: true and ESNext target, initializer
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// expressions for property declarations are evaluated in the scope of
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// the class body and are permitted to reference parameters or local
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// variables of the constructor. This is different from classic
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// Typescript behaviour, with useDefineForClassFields: false. There,
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// initialisers of property declarations are evaluated in the scope of
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// the constructor body.
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// Note that when class fields are accepted in the ECMAScript
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// standard, the target will become that year's ES20xx
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var x = 1;
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class C {
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b = x; // ok
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constructor(x: string) {
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}
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}
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var y = 1;
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class D {
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b = y; // ok
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constructor(x: string) {
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var y = "";
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}
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}
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class E {
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b = z; // not ok
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constructor(z: string) {
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}
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}
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