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=== tests/cases/conformance/es6/destructuring/destructuringParameterDeclaration2.ts ===
// A parameter declaration may specify either an identifier or a binding pattern.
// The identifiers specified in parameter declarations and binding patterns
// in a parameter list must be unique within that parameter list.
// If the declaration includes a type annotation, the parameter is of that type
function a0([a, b, [[c]]]: [number, number, string[][]]) { }
>a0 : Symbol(a0, Decl(destructuringParameterDeclaration2.ts, 0, 0))
>a : Symbol(a, Decl(destructuringParameterDeclaration2.ts, 5, 13))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 5, 15))
>c : Symbol(c, Decl(destructuringParameterDeclaration2.ts, 5, 21))
a0([1, "string", [["world"]]); // Error
>a0 : Symbol(a0, Decl(destructuringParameterDeclaration2.ts, 0, 0))
a0([1, 2, [["world"]], "string"]); // Error
>a0 : Symbol(a0, Decl(destructuringParameterDeclaration2.ts, 0, 0))
// If the declaration includes an initializer expression (which is permitted only
// when the parameter list occurs in conjunction with a function body),
// the parameter type is the widened form (section 3.11) of the type of the initializer expression.
interface F1 {
>F1 : Symbol(F1, Decl(destructuringParameterDeclaration2.ts, 7, 34))
b0(z = 10, [[a, b], d, {u}] = [[1, 2], "string", { u: false }]); // Error, no function body
>b0 : Symbol(F1.b0, Decl(destructuringParameterDeclaration2.ts, 14, 14))
>z : Symbol(z, Decl(destructuringParameterDeclaration2.ts, 15, 7))
>a : Symbol(a, Decl(destructuringParameterDeclaration2.ts, 15, 17))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 15, 19))
>d : Symbol(d, Decl(destructuringParameterDeclaration2.ts, 15, 23))
>u : Symbol(u, Decl(destructuringParameterDeclaration2.ts, 15, 28))
>u : Symbol(u, Decl(destructuringParameterDeclaration2.ts, 15, 54))
}
function b1(z = null, o = { x: 0, y: undefined }) { }
>b1 : Symbol(b1, Decl(destructuringParameterDeclaration2.ts, 16, 1))
>z : Symbol(z, Decl(destructuringParameterDeclaration2.ts, 18, 12))
>o : Symbol(o, Decl(destructuringParameterDeclaration2.ts, 18, 21))
>x : Symbol(x, Decl(destructuringParameterDeclaration2.ts, 18, 27))
>y : Symbol(y, Decl(destructuringParameterDeclaration2.ts, 18, 33))
>undefined : Symbol(undefined)
function b2([a, z, y] = [undefined, null, undefined]) { }
>b2 : Symbol(b2, Decl(destructuringParameterDeclaration2.ts, 18, 53))
>a : Symbol(a, Decl(destructuringParameterDeclaration2.ts, 19, 13))
>z : Symbol(z, Decl(destructuringParameterDeclaration2.ts, 19, 15))
>y : Symbol(y, Decl(destructuringParameterDeclaration2.ts, 19, 18))
>undefined : Symbol(undefined)
>undefined : Symbol(undefined)
function b3([[a], b, [[c, d]]] = [[undefined], undefined, [[undefined, undefined]]]) { }
>b3 : Symbol(b3, Decl(destructuringParameterDeclaration2.ts, 19, 57))
>a : Symbol(a, Decl(destructuringParameterDeclaration2.ts, 20, 14))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 20, 17))
>c : Symbol(c, Decl(destructuringParameterDeclaration2.ts, 20, 23))
>d : Symbol(d, Decl(destructuringParameterDeclaration2.ts, 20, 25))
>undefined : Symbol(undefined)
>undefined : Symbol(undefined)
>undefined : Symbol(undefined)
>undefined : Symbol(undefined)
b1("string", { x: "string", y: true }); // Error
>b1 : Symbol(b1, Decl(destructuringParameterDeclaration2.ts, 16, 1))
>x : Symbol(x, Decl(destructuringParameterDeclaration2.ts, 22, 14))
>y : Symbol(y, Decl(destructuringParameterDeclaration2.ts, 22, 27))
// If the declaration specifies a binding pattern, the parameter type is the implied type of that binding pattern (section 5.1.3)
function c0({z: {x, y: {j}}}) { }
>c0 : Symbol(c0, Decl(destructuringParameterDeclaration2.ts, 22, 39))
>z : Symbol(z)
>x : Symbol(x, Decl(destructuringParameterDeclaration2.ts, 25, 17))
>y : Symbol(y)
>j : Symbol(j, Decl(destructuringParameterDeclaration2.ts, 25, 24))
function c1({z} = { z: 10 }) { }
>c1 : Symbol(c1, Decl(destructuringParameterDeclaration2.ts, 25, 33))
>z : Symbol(z, Decl(destructuringParameterDeclaration2.ts, 26, 13))
>z : Symbol(z, Decl(destructuringParameterDeclaration2.ts, 26, 19))
function c2({z = 10}) { }
>c2 : Symbol(c2, Decl(destructuringParameterDeclaration2.ts, 26, 32))
>z : Symbol(z, Decl(destructuringParameterDeclaration2.ts, 27, 13))
function c3({b}: { b: number|string } = { b: "hello" }) { }
>c3 : Symbol(c3, Decl(destructuringParameterDeclaration2.ts, 27, 25))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 28, 13))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 28, 18))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 28, 41))
function c4([z], z: number) { } // Error Duplicate identifier
>c4 : Symbol(c4, Decl(destructuringParameterDeclaration2.ts, 28, 59))
>z : Symbol(z, Decl(destructuringParameterDeclaration2.ts, 29, 13))
>z : Symbol(z, Decl(destructuringParameterDeclaration2.ts, 29, 16))
function c5([a, b, [[c]]]) { }
>c5 : Symbol(c5, Decl(destructuringParameterDeclaration2.ts, 29, 31))
>a : Symbol(a, Decl(destructuringParameterDeclaration2.ts, 30, 13))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 30, 15))
>c : Symbol(c, Decl(destructuringParameterDeclaration2.ts, 30, 21))
function c6([a, b, [[c = 1]]]) { }
>c6 : Symbol(c6, Decl(destructuringParameterDeclaration2.ts, 30, 30))
>a : Symbol(a, Decl(destructuringParameterDeclaration2.ts, 31, 13))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 31, 15))
>c : Symbol(c, Decl(destructuringParameterDeclaration2.ts, 31, 21))
c0({ z: 1 }); // Error, implied type is { z: {x: any, y: {j: any}} }
>c0 : Symbol(c0, Decl(destructuringParameterDeclaration2.ts, 22, 39))
>z : Symbol(z, Decl(destructuringParameterDeclaration2.ts, 33, 4))
c1({}); // Error, implied type is {z:number}?
>c1 : Symbol(c1, Decl(destructuringParameterDeclaration2.ts, 25, 33))
c1({ z: true }); // Error, implied type is {z:number}?
>c1 : Symbol(c1, Decl(destructuringParameterDeclaration2.ts, 25, 33))
>z : Symbol(z, Decl(destructuringParameterDeclaration2.ts, 35, 4))
c2({ z: false }); // Error, implied type is {z?: number}
>c2 : Symbol(c2, Decl(destructuringParameterDeclaration2.ts, 26, 32))
>z : Symbol(z, Decl(destructuringParameterDeclaration2.ts, 36, 4))
c3({ b: true }); // Error, implied type is { b: number|string }.
>c3 : Symbol(c3, Decl(destructuringParameterDeclaration2.ts, 27, 25))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 37, 4))
c5([1, 2, false, true]); // Error, implied type is [any, any, [[any]]]
>c5 : Symbol(c5, Decl(destructuringParameterDeclaration2.ts, 29, 31))
c6([1, 2, [["string"]]]); // Error, implied type is [any, any, [[number]]] // Use initializer
>c6 : Symbol(c6, Decl(destructuringParameterDeclaration2.ts, 30, 30))
// A parameter can be marked optional by following its name or binding pattern with a question mark (?)
// or by including an initializer. Initializers (including binding property or element initializers) are
// permitted only when the parameter list occurs in conjunction with a function body
function d1([a, b, c]?) { } // Error, binding pattern can't be optional in implementation signature
>d1 : Symbol(d1, Decl(destructuringParameterDeclaration2.ts, 39, 25))
>a : Symbol(a, Decl(destructuringParameterDeclaration2.ts, 45, 13))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 45, 15))
>c : Symbol(c, Decl(destructuringParameterDeclaration2.ts, 45, 18))
function d2({x, y, z}?) { } // Error, binding pattern can't be optional in implementation signature
>d2 : Symbol(d2, Decl(destructuringParameterDeclaration2.ts, 45, 27))
>x : Symbol(x, Decl(destructuringParameterDeclaration2.ts, 46, 13))
>y : Symbol(y, Decl(destructuringParameterDeclaration2.ts, 46, 15))
>z : Symbol(z, Decl(destructuringParameterDeclaration2.ts, 46, 18))
interface F2 {
>F2 : Symbol(F2, Decl(destructuringParameterDeclaration2.ts, 46, 27))
d3([a, b, c]?);
>d3 : Symbol(F2.d3, Decl(destructuringParameterDeclaration2.ts, 48, 14))
>a : Symbol(a, Decl(destructuringParameterDeclaration2.ts, 49, 8))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 49, 10))
>c : Symbol(c, Decl(destructuringParameterDeclaration2.ts, 49, 13))
d4({x, y, z}?);
>d4 : Symbol(F2.d4, Decl(destructuringParameterDeclaration2.ts, 49, 19))
>x : Symbol(x, Decl(destructuringParameterDeclaration2.ts, 50, 8))
>y : Symbol(y, Decl(destructuringParameterDeclaration2.ts, 50, 10))
>z : Symbol(z, Decl(destructuringParameterDeclaration2.ts, 50, 13))
e0([a, b, c]);
>e0 : Symbol(F2.e0, Decl(destructuringParameterDeclaration2.ts, 50, 19))
>a : Symbol(a, Decl(destructuringParameterDeclaration2.ts, 51, 8))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 51, 10))
>c : Symbol(c, Decl(destructuringParameterDeclaration2.ts, 51, 13))
}
class C4 implements F2 {
>C4 : Symbol(C4, Decl(destructuringParameterDeclaration2.ts, 52, 1))
>F2 : Symbol(F2, Decl(destructuringParameterDeclaration2.ts, 46, 27))
d3([a, b, c]?) { } // Error, binding pattern can't be optional in implementation signature
>d3 : Symbol(C4.d3, Decl(destructuringParameterDeclaration2.ts, 54, 24))
>a : Symbol(a, Decl(destructuringParameterDeclaration2.ts, 55, 8))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 55, 10))
>c : Symbol(c, Decl(destructuringParameterDeclaration2.ts, 55, 13))
d4({x, y, c}) { }
>d4 : Symbol(C4.d4, Decl(destructuringParameterDeclaration2.ts, 55, 22))
>x : Symbol(x, Decl(destructuringParameterDeclaration2.ts, 56, 8))
>y : Symbol(y, Decl(destructuringParameterDeclaration2.ts, 56, 10))
>c : Symbol(c, Decl(destructuringParameterDeclaration2.ts, 56, 13))
e0([a, b, q]) { }
>e0 : Symbol(C4.e0, Decl(destructuringParameterDeclaration2.ts, 56, 21))
>a : Symbol(a, Decl(destructuringParameterDeclaration2.ts, 57, 8))
>b : Symbol(b, Decl(destructuringParameterDeclaration2.ts, 57, 10))
>q : Symbol(q, Decl(destructuringParameterDeclaration2.ts, 57, 13))
}
// Destructuring parameter declarations do not permit type annotations on the individual binding patterns,
// as such annotations would conflict with the already established meaning of colons in object literals.
// Type annotations must instead be written on the top- level parameter declaration
function e0({x: [number, number, number]}) { } // error, duplicate identifier;
>e0 : Symbol(e0, Decl(destructuringParameterDeclaration2.ts, 58, 1))
>x : Symbol(x)
>number : Symbol(number, Decl(destructuringParameterDeclaration2.ts, 64, 17))
>number : Symbol(number, Decl(destructuringParameterDeclaration2.ts, 64, 24))
>number : Symbol(number, Decl(destructuringParameterDeclaration2.ts, 64, 32))
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