diff --git a/tests/baselines/reference/declarationInAmbientContext.errors.txt b/tests/baselines/reference/declarationInAmbientContext.errors.txt
new file mode 100644
index 0000000000..85e8808a27
--- /dev/null
+++ b/tests/baselines/reference/declarationInAmbientContext.errors.txt
@@ -0,0 +1,12 @@
+tests/cases/conformance/es6/destructuring/declarationInAmbientContext.ts(1,13): error TS1166: Destructuring declarations are not allowed in ambient contexts.
+tests/cases/conformance/es6/destructuring/declarationInAmbientContext.ts(2,13): error TS1166: Destructuring declarations are not allowed in ambient contexts.
+
+
+==== tests/cases/conformance/es6/destructuring/declarationInAmbientContext.ts (2 errors) ====
+    declare var [a, b];  // Error, destructuring declaration not allowed in ambient context
+                ~~~~~~
+!!! error TS1166: Destructuring declarations are not allowed in ambient contexts.
+    declare var {c, d};  // Error, destructuring declaration not allowed in ambient context
+                ~~~~~~
+!!! error TS1166: Destructuring declarations are not allowed in ambient contexts.
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/declarationWithNoInitializer.errors.txt b/tests/baselines/reference/declarationWithNoInitializer.errors.txt
new file mode 100644
index 0000000000..6d5c2022a9
--- /dev/null
+++ b/tests/baselines/reference/declarationWithNoInitializer.errors.txt
@@ -0,0 +1,12 @@
+tests/cases/conformance/es6/destructuring/declarationWithNoInitializer.ts(1,5): error TS1165: A destructuring declaration must have an initializer.
+tests/cases/conformance/es6/destructuring/declarationWithNoInitializer.ts(2,5): error TS1165: A destructuring declaration must have an initializer.
+
+
+==== tests/cases/conformance/es6/destructuring/declarationWithNoInitializer.ts (2 errors) ====
+    var [a, b];          // Error, no initializer
+        ~~~~~~
+!!! error TS1165: A destructuring declaration must have an initializer.
+    var {c, d};          // Error, no initializer
+        ~~~~~~
+!!! error TS1165: A destructuring declaration must have an initializer.
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/declarationsAndAssignments.errors.txt b/tests/baselines/reference/declarationsAndAssignments.errors.txt
new file mode 100644
index 0000000000..2c9a54c869
--- /dev/null
+++ b/tests/baselines/reference/declarationsAndAssignments.errors.txt
@@ -0,0 +1,202 @@
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(5,16): error TS2460: Type '[number, string]' has no property '2'.
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(56,17): error TS2322: Type 'number' is not assignable to type 'string'.
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(63,13): error TS2460: Type '[number]' has no property '1'.
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(63,16): error TS2460: Type '[number]' has no property '2'.
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(67,9): error TS2461: Type '{ [x: number]: undefined; }' is not an array type.
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(68,9): error TS2461: Type '{ [x: number]: number; 0: number; 1: number; }' is not an array type.
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(73,11): error TS2459: Type '{}' has no property 'a' and no string index signature.
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(73,14): error TS2459: Type '{}' has no property 'b' and no string index signature.
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(74,11): error TS2459: Type 'undefined[]' has no property 'a' and no string index signature.
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(74,14): error TS2459: Type 'undefined[]' has no property 'b' and no string index signature.
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(106,5): error TS2345: Argument of type '[number, [string, { y: boolean; }]]' is not assignable to parameter of type '[number, [string, { x: any; y?: boolean; }]]'.
+  Types of property '1' are incompatible.
+    Type '[string, { y: boolean; }]' is not assignable to type '[string, { x: any; y?: boolean; }]'.
+      Types of property '1' are incompatible.
+        Type '{ y: boolean; }' is not assignable to type '{ x: any; y?: boolean; }'.
+          Property 'x' is missing in type '{ y: boolean; }'.
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(138,6): error TS2322: Type 'string' is not assignable to type 'number'.
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(138,9): error TS2322: Type 'number' is not assignable to type 'string'.
+
+
+==== tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts (13 errors) ====
+    function f0() {
+        var [] = [1, "hello"];
+        var [x] = [1, "hello"];
+        var [x, y] = [1, "hello"];
+        var [x, y, z] = [1, "hello"];  // Error
+                   ~
+!!! error TS2460: Type '[number, string]' has no property '2'.
+        var [,, z] = [0, 1, 2];
+        var x: number;
+        var y: string;
+    }
+    
+    function f1() {
+        var a = [1, "hello"];
+        var [x] = a;
+        var [x, y] = a;
+        var [x, y, z] = a;
+        var x: number | string;
+        var y: number | string;
+        var z: number | string;
+    }
+    
+    function f2() {
+        var { } = { x: 5, y: "hello" };
+        var { x } = { x: 5, y: "hello" };
+        var { y } = { x: 5, y: "hello" };
+        var { x, y } = { x: 5, y: "hello" };
+        var x: number;
+        var y: string;
+        var { x: a } = { x: 5, y: "hello" };
+        var { y: b } = { x: 5, y: "hello" };
+        var { x: a, y: b } = { x: 5, y: "hello" };
+        var a: number;
+        var b: string;
+    }
+    
+    function f3() {
+        var [x, [y, [z]]] = [1, ["hello", [true]]];
+        var x: number;
+        var y: string;
+        var z: boolean;
+    }
+    
+    function f4() {
+        var { a: x, b: { a: y, b: { a: z }}} = { a: 1, b: { a: "hello", b: { a: true } } };
+        var x: number;
+        var y: string;
+        var z: boolean;
+    }
+    
+    function f6() {
+        var [x = 0, y = ""] = [1, "hello"];
+        var x: number;
+        var y: string;
+    }
+    
+    function f7() {
+        var [x = 0, y = 1] = [1, "hello"];  // Error, initializer for y must be string
+                    ~
+!!! error TS2322: Type 'number' is not assignable to type 'string'.
+        var x: number;
+        var y: string;
+    }
+    
+    function f8() {
+        var [a, b, c] = [];   // Ok, [] is an array
+        var [d, e, f] = [1];  // Error, [1] is a tuple
+                ~
+!!! error TS2460: Type '[number]' has no property '1'.
+                   ~
+!!! error TS2460: Type '[number]' has no property '2'.
+    }
+    
+    function f9() {
+        var [a, b] = {};                // Error, not array type
+            ~~~~~~
+!!! error TS2461: Type '{ [x: number]: undefined; }' is not an array type.
+        var [c, d] = { 0: 10, 1: 20 };  // Error, not array type
+            ~~~~~~
+!!! error TS2461: Type '{ [x: number]: number; 0: number; 1: number; }' is not an array type.
+        var [e, f] = [10, 20];
+    }
+    
+    function f10() {
+        var { a, b } = {};  // Error
+              ~
+!!! error TS2459: Type '{}' has no property 'a' and no string index signature.
+                 ~
+!!! error TS2459: Type '{}' has no property 'b' and no string index signature.
+        var { a, b } = [];  // Error
+              ~
+!!! error TS2459: Type 'undefined[]' has no property 'a' and no string index signature.
+                 ~
+!!! error TS2459: Type 'undefined[]' has no property 'b' and no string index signature.
+    }
+    
+    function f11() {
+        var { x: a, y: b } = { x: 10, y: "hello" };
+        var { 0: a, 1: b } = { 0: 10, 1: "hello" };
+        var { "<": a, ">": b } = { "<": 10, ">": "hello" };
+        var { 0: a, 1: b } = [10, "hello"];
+        var a: number;
+        var b: string;
+    }
+    
+    function f12() {
+        var [a, [b, { x, y: c }] = ["abc", { x: 10, y: false }]] = [1, ["hello", { x: 5, y: true }]];
+        var a: number;
+        var b: string;
+        var x: number;
+        var c: boolean;
+    }
+    
+    function f13() {
+        var [x, y] = [1, "hello"];
+        var [a, b] = [[x, y], { x: x, y: y }];
+    }
+    
+    function f14([a = 1, [b = "hello", { x, y: c = false }]]) {
+        var a: number;
+        var b: string;
+        var c: boolean;
+    }
+    f14([2, ["abc", { x: 0, y: true }]]);
+    f14([2, ["abc", { x: 0 }]]);
+    f14([2, ["abc", { y: false }]]);  // Error, no x
+        ~~~~~~~~~~~~~~~~~~~~~~~~~~
+!!! error TS2345: Argument of type '[number, [string, { y: boolean; }]]' is not assignable to parameter of type '[number, [string, { x: any; y?: boolean; }]]'.
+!!! error TS2345:   Types of property '1' are incompatible.
+!!! error TS2345:     Type '[string, { y: boolean; }]' is not assignable to type '[string, { x: any; y?: boolean; }]'.
+!!! error TS2345:       Types of property '1' are incompatible.
+!!! error TS2345:         Type '{ y: boolean; }' is not assignable to type '{ x: any; y?: boolean; }'.
+!!! error TS2345:           Property 'x' is missing in type '{ y: boolean; }'.
+    
+    module M {
+        export var [a, b] = [1, 2];
+    }
+    
+    function f15() {
+        var a = "hello";
+        var b = 1;
+        var c = true;
+        return { a, b, c };
+    }
+    
+    function f16() {
+        var { a, b, c } = f15();
+    }
+    
+    function f17({ a = "", b = 0, c = false }) {
+    }
+    
+    f17({});
+    f17({ a: "hello" });
+    f17({ c: true });
+    f17(f15());
+    
+    function g4() {
+        var a: number;
+        var b: string;
+        var aa: number[];
+        ({ a, b } = { a, b });
+        ({ a, b } = { b, a });
+        [aa[0], b] = [a, b];
+        [a, b] = [b, a];  // Error
+         ~
+!!! error TS2322: Type 'string' is not assignable to type 'number'.
+            ~
+!!! error TS2322: Type 'number' is not assignable to type 'string'.
+        [a = 1, b = "abc"] = [2, "def"];
+    }
+    
+    function g5() {
+        var a, b;
+        [a, b] = [1, 2];
+        [a, b] = [b, a];
+        ({ a, b } = { b, a });
+        [[a, b] = [1, 2]] = [[2, 3]];
+        var x = ([a, b] = [1, 2]);
+    }
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/declarationsAndAssignments.js b/tests/baselines/reference/declarationsAndAssignments.js
new file mode 100644
index 0000000000..ba2e74dc42
--- /dev/null
+++ b/tests/baselines/reference/declarationsAndAssignments.js
@@ -0,0 +1,288 @@
+//// [declarationsAndAssignments.ts]
+function f0() {
+    var [] = [1, "hello"];
+    var [x] = [1, "hello"];
+    var [x, y] = [1, "hello"];
+    var [x, y, z] = [1, "hello"];  // Error
+    var [,, z] = [0, 1, 2];
+    var x: number;
+    var y: string;
+}
+
+function f1() {
+    var a = [1, "hello"];
+    var [x] = a;
+    var [x, y] = a;
+    var [x, y, z] = a;
+    var x: number | string;
+    var y: number | string;
+    var z: number | string;
+}
+
+function f2() {
+    var { } = { x: 5, y: "hello" };
+    var { x } = { x: 5, y: "hello" };
+    var { y } = { x: 5, y: "hello" };
+    var { x, y } = { x: 5, y: "hello" };
+    var x: number;
+    var y: string;
+    var { x: a } = { x: 5, y: "hello" };
+    var { y: b } = { x: 5, y: "hello" };
+    var { x: a, y: b } = { x: 5, y: "hello" };
+    var a: number;
+    var b: string;
+}
+
+function f3() {
+    var [x, [y, [z]]] = [1, ["hello", [true]]];
+    var x: number;
+    var y: string;
+    var z: boolean;
+}
+
+function f4() {
+    var { a: x, b: { a: y, b: { a: z }}} = { a: 1, b: { a: "hello", b: { a: true } } };
+    var x: number;
+    var y: string;
+    var z: boolean;
+}
+
+function f6() {
+    var [x = 0, y = ""] = [1, "hello"];
+    var x: number;
+    var y: string;
+}
+
+function f7() {
+    var [x = 0, y = 1] = [1, "hello"];  // Error, initializer for y must be string
+    var x: number;
+    var y: string;
+}
+
+function f8() {
+    var [a, b, c] = [];   // Ok, [] is an array
+    var [d, e, f] = [1];  // Error, [1] is a tuple
+}
+
+function f9() {
+    var [a, b] = {};                // Error, not array type
+    var [c, d] = { 0: 10, 1: 20 };  // Error, not array type
+    var [e, f] = [10, 20];
+}
+
+function f10() {
+    var { a, b } = {};  // Error
+    var { a, b } = [];  // Error
+}
+
+function f11() {
+    var { x: a, y: b } = { x: 10, y: "hello" };
+    var { 0: a, 1: b } = { 0: 10, 1: "hello" };
+    var { "<": a, ">": b } = { "<": 10, ">": "hello" };
+    var { 0: a, 1: b } = [10, "hello"];
+    var a: number;
+    var b: string;
+}
+
+function f12() {
+    var [a, [b, { x, y: c }] = ["abc", { x: 10, y: false }]] = [1, ["hello", { x: 5, y: true }]];
+    var a: number;
+    var b: string;
+    var x: number;
+    var c: boolean;
+}
+
+function f13() {
+    var [x, y] = [1, "hello"];
+    var [a, b] = [[x, y], { x: x, y: y }];
+}
+
+function f14([a = 1, [b = "hello", { x, y: c = false }]]) {
+    var a: number;
+    var b: string;
+    var c: boolean;
+}
+f14([2, ["abc", { x: 0, y: true }]]);
+f14([2, ["abc", { x: 0 }]]);
+f14([2, ["abc", { y: false }]]);  // Error, no x
+
+module M {
+    export var [a, b] = [1, 2];
+}
+
+function f15() {
+    var a = "hello";
+    var b = 1;
+    var c = true;
+    return { a, b, c };
+}
+
+function f16() {
+    var { a, b, c } = f15();
+}
+
+function f17({ a = "", b = 0, c = false }) {
+}
+
+f17({});
+f17({ a: "hello" });
+f17({ c: true });
+f17(f15());
+
+function g4() {
+    var a: number;
+    var b: string;
+    var aa: number[];
+    ({ a, b } = { a, b });
+    ({ a, b } = { b, a });
+    [aa[0], b] = [a, b];
+    [a, b] = [b, a];  // Error
+    [a = 1, b = "abc"] = [2, "def"];
+}
+
+function g5() {
+    var a, b;
+    [a, b] = [1, 2];
+    [a, b] = [b, a];
+    ({ a, b } = { b, a });
+    [[a, b] = [1, 2]] = [[2, 3]];
+    var x = ([a, b] = [1, 2]);
+}
+
+
+//// [declarationsAndAssignments.js]
+function f0() {
+    var _a = [1, "hello"];
+    var x = ([1, "hello"])[0];
+    var _b = [1, "hello"], x = _b[0], y = _b[1];
+    var _c = [1, "hello"], x = _c[0], y = _c[1], z = _c[2]; // Error
+    var _d = [0, 1, 2], z = _d[2];
+    var x;
+    var y;
+}
+function f1() {
+    var a = [1, "hello"];
+    var x = a[0];
+    var x = a[0], y = a[1];
+    var x = a[0], y = a[1], z = a[2];
+    var x;
+    var y;
+    var z;
+}
+function f2() {
+    var _a = { x: 5, y: "hello" };
+    var x = ({ x: 5, y: "hello" }).x;
+    var y = ({ x: 5, y: "hello" }).y;
+    var _b = { x: 5, y: "hello" }, x = _b.x, y = _b.y;
+    var x;
+    var y;
+    var a = ({ x: 5, y: "hello" }).x;
+    var b = ({ x: 5, y: "hello" }).y;
+    var _c = { x: 5, y: "hello" }, a = _c.x, b = _c.y;
+    var a;
+    var b;
+}
+function f3() {
+    var _a = [1, ["hello", [true]]], x = _a[0], _b = _a[1], y = _b[0], z = _b[1][0];
+    var x;
+    var y;
+    var z;
+}
+function f4() {
+    var _a = { a: 1, b: { a: "hello", b: { a: true } } }, x = _a.a, _b = _a.b, y = _b.a, z = _b.b.a;
+    var x;
+    var y;
+    var z;
+}
+function f6() {
+    var _a = [1, "hello"], _b = _a[0], x = _b === void 0 ? 0 : _b, _c = _a[1], y = _c === void 0 ? "" : _c;
+    var x;
+    var y;
+}
+function f7() {
+    var _a = [1, "hello"], _b = _a[0], x = _b === void 0 ? 0 : _b, _c = _a[1], y = _c === void 0 ? 1 : _c; // Error, initializer for y must be string
+    var x;
+    var y;
+}
+function f8() {
+    var _a = [], a = _a[0], b = _a[1], c = _a[2]; // Ok, [] is an array
+    var _b = [1], d = _b[0], e = _b[1], f = _b[2]; // Error, [1] is a tuple
+}
+function f9() {
+    var _a = {}, a = _a[0], b = _a[1]; // Error, not array type
+    var _b = { 0: 10, 1: 20 }, c = _b[0], d = _b[1]; // Error, not array type
+    var _c = [10, 20], e = _c[0], f = _c[1];
+}
+function f10() {
+    var _a = {}, a = _a.a, b = _a.b; // Error
+    var _b = [], a = _b.a, b = _b.b; // Error
+}
+function f11() {
+    var _a = { x: 10, y: "hello" }, a = _a.x, b = _a.y;
+    var _b = { 0: 10, 1: "hello" }, a = _b[0], b = _b[1];
+    var _c = { "<": 10, ">": "hello" }, a = _c["<"], b = _c[">"];
+    var _d = [10, "hello"], a = _d[0], b = _d[1];
+    var a;
+    var b;
+}
+function f12() {
+    var _a = [1, ["hello", { x: 5, y: true }]], a = _a[0], _b = _a[1], _c = _b === void 0 ? ["abc", { x: 10, y: false }] : _b, b = _c[0], _d = _c[1], x = _d.x, c = _d.y;
+    var a;
+    var b;
+    var x;
+    var c;
+}
+function f13() {
+    var _a = [1, "hello"], x = _a[0], y = _a[1];
+    var _b = [[x, y], { x: x, y: y }], a = _b[0], b = _b[1];
+}
+function f14(_a) {
+    var _b = _a[0], a = _b === void 0 ? 1 : _b, _c = _a[1], _d = _c[0], b = _d === void 0 ? "hello" : _d, _e = _c[1], x = _e.x, _f = _e.y, c = _f === void 0 ? false : _f;
+    var a;
+    var b;
+    var c;
+}
+f14([2, ["abc", { x: 0, y: true }]]);
+f14([2, ["abc", { x: 0 }]]);
+f14([2, ["abc", { y: false }]]); // Error, no x
+var M;
+(function (M) {
+    _a = [1, 2], M.a = _a[0], M.b = _a[1];
+    var _a;
+})(M || (M = {}));
+function f15() {
+    var a = "hello";
+    var b = 1;
+    var c = true;
+    return { a: a, b: b, c: c };
+}
+function f16() {
+    var _a = f15(), a = _a.a, b = _a.b, c = _a.c;
+}
+function f17(_a) {
+    var _b = _a.a, a = _b === void 0 ? "" : _b, _c = _a.b, b = _c === void 0 ? 0 : _c, _d = _a.c, c = _d === void 0 ? false : _d;
+}
+f17({});
+f17({ a: "hello" });
+f17({ c: true });
+f17(f15());
+function g4() {
+    var a;
+    var b;
+    var aa;
+    (_a = { a: a, b: b }, a = _a.a, b = _a.b, _a);
+    (_b = { b: b, a: a }, a = _b.a, b = _b.b, _b);
+    _c = [a, b], aa[0] = _c[0], b = _c[1];
+    _d = [b, a], a = _d[0], b = _d[1]; // Error
+    _e = [2, "def"], _f = _e[0], a = _f === void 0 ? 1 : _f, _g = _e[1], b = _g === void 0 ? "abc" : _g;
+    var _a, _b, _c, _d, _e, _f, _g;
+}
+function g5() {
+    var a, b;
+    _a = [1, 2], a = _a[0], b = _a[1];
+    _b = [b, a], a = _b[0], b = _b[1];
+    (_c = { b: b, a: a }, a = _c.a, b = _c.b, _c);
+    _d = ([[2, 3]])[0], _e = _d === void 0 ? [1, 2] : _d, a = _e[0], b = _e[1];
+    var x = (_f = [1, 2], a = _f[0], b = _f[1], _f);
+    var _a, _b, _c, _d, _e, _f;
+}
diff --git a/tests/cases/conformance/es6/destructuring/declarationInAmbientContext.ts b/tests/cases/conformance/es6/destructuring/declarationInAmbientContext.ts
new file mode 100644
index 0000000000..a3db3753de
--- /dev/null
+++ b/tests/cases/conformance/es6/destructuring/declarationInAmbientContext.ts
@@ -0,0 +1,2 @@
+declare var [a, b];  // Error, destructuring declaration not allowed in ambient context
+declare var {c, d};  // Error, destructuring declaration not allowed in ambient context
diff --git a/tests/cases/conformance/es6/destructuring/declarationWithNoInitializer.ts b/tests/cases/conformance/es6/destructuring/declarationWithNoInitializer.ts
new file mode 100644
index 0000000000..1fb8b07e58
--- /dev/null
+++ b/tests/cases/conformance/es6/destructuring/declarationWithNoInitializer.ts
@@ -0,0 +1,2 @@
+var [a, b];          // Error, no initializer
+var {c, d};          // Error, no initializer
diff --git a/tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts b/tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts
new file mode 100644
index 0000000000..04cdd153a5
--- /dev/null
+++ b/tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts
@@ -0,0 +1,149 @@
+function f0() {
+    var [] = [1, "hello"];
+    var [x] = [1, "hello"];
+    var [x, y] = [1, "hello"];
+    var [x, y, z] = [1, "hello"];  // Error
+    var [,, z] = [0, 1, 2];
+    var x: number;
+    var y: string;
+}
+
+function f1() {
+    var a = [1, "hello"];
+    var [x] = a;
+    var [x, y] = a;
+    var [x, y, z] = a;
+    var x: number | string;
+    var y: number | string;
+    var z: number | string;
+}
+
+function f2() {
+    var { } = { x: 5, y: "hello" };
+    var { x } = { x: 5, y: "hello" };
+    var { y } = { x: 5, y: "hello" };
+    var { x, y } = { x: 5, y: "hello" };
+    var x: number;
+    var y: string;
+    var { x: a } = { x: 5, y: "hello" };
+    var { y: b } = { x: 5, y: "hello" };
+    var { x: a, y: b } = { x: 5, y: "hello" };
+    var a: number;
+    var b: string;
+}
+
+function f3() {
+    var [x, [y, [z]]] = [1, ["hello", [true]]];
+    var x: number;
+    var y: string;
+    var z: boolean;
+}
+
+function f4() {
+    var { a: x, b: { a: y, b: { a: z }}} = { a: 1, b: { a: "hello", b: { a: true } } };
+    var x: number;
+    var y: string;
+    var z: boolean;
+}
+
+function f6() {
+    var [x = 0, y = ""] = [1, "hello"];
+    var x: number;
+    var y: string;
+}
+
+function f7() {
+    var [x = 0, y = 1] = [1, "hello"];  // Error, initializer for y must be string
+    var x: number;
+    var y: string;
+}
+
+function f8() {
+    var [a, b, c] = [];   // Ok, [] is an array
+    var [d, e, f] = [1];  // Error, [1] is a tuple
+}
+
+function f9() {
+    var [a, b] = {};                // Error, not array type
+    var [c, d] = { 0: 10, 1: 20 };  // Error, not array type
+    var [e, f] = [10, 20];
+}
+
+function f10() {
+    var { a, b } = {};  // Error
+    var { a, b } = [];  // Error
+}
+
+function f11() {
+    var { x: a, y: b } = { x: 10, y: "hello" };
+    var { 0: a, 1: b } = { 0: 10, 1: "hello" };
+    var { "<": a, ">": b } = { "<": 10, ">": "hello" };
+    var { 0: a, 1: b } = [10, "hello"];
+    var a: number;
+    var b: string;
+}
+
+function f12() {
+    var [a, [b, { x, y: c }] = ["abc", { x: 10, y: false }]] = [1, ["hello", { x: 5, y: true }]];
+    var a: number;
+    var b: string;
+    var x: number;
+    var c: boolean;
+}
+
+function f13() {
+    var [x, y] = [1, "hello"];
+    var [a, b] = [[x, y], { x: x, y: y }];
+}
+
+function f14([a = 1, [b = "hello", { x, y: c = false }]]) {
+    var a: number;
+    var b: string;
+    var c: boolean;
+}
+f14([2, ["abc", { x: 0, y: true }]]);
+f14([2, ["abc", { x: 0 }]]);
+f14([2, ["abc", { y: false }]]);  // Error, no x
+
+module M {
+    export var [a, b] = [1, 2];
+}
+
+function f15() {
+    var a = "hello";
+    var b = 1;
+    var c = true;
+    return { a, b, c };
+}
+
+function f16() {
+    var { a, b, c } = f15();
+}
+
+function f17({ a = "", b = 0, c = false }) {
+}
+
+f17({});
+f17({ a: "hello" });
+f17({ c: true });
+f17(f15());
+
+function g4() {
+    var a: number;
+    var b: string;
+    var aa: number[];
+    ({ a, b } = { a, b });
+    ({ a, b } = { b, a });
+    [aa[0], b] = [a, b];
+    [a, b] = [b, a];  // Error
+    [a = 1, b = "abc"] = [2, "def"];
+}
+
+function g5() {
+    var a, b;
+    [a, b] = [1, 2];
+    [a, b] = [b, a];
+    ({ a, b } = { b, a });
+    [[a, b] = [1, 2]] = [[2, 3]];
+    var x = ([a, b] = [1, 2]);
+}