Merge pull request #2792 from Microsoft/conformanceConstEnum

Conformance for spec update section 9.4, 12.1.4 const enum

tests/baselines/reference/ambientEnumDeclaration1.errors.txt

@@ -0,0 +1,24 @@
+tests/cases/conformance/ambient/ambientEnumDeclaration1.ts(5,5): error TS1066: Ambient enum elements can only have integer literal initializers.
+tests/cases/conformance/ambient/ambientEnumDeclaration1.ts(6,5): error TS1066: Ambient enum elements can only have integer literal initializers.
+tests/cases/conformance/ambient/ambientEnumDeclaration1.ts(7,5): error TS1066: Ambient enum elements can only have integer literal initializers.
+tests/cases/conformance/ambient/ambientEnumDeclaration1.ts(8,5): error TS1066: Ambient enum elements can only have integer literal initializers.
+
+
+==== tests/cases/conformance/ambient/ambientEnumDeclaration1.ts (4 errors) ====
+    // In ambient enum declarations, all values specified in enum member declarations must be classified as constant enum expressions.
+    
+    declare enum E {
+        a = 10,
+        b = 10 + 1,
+        ~
+!!! error TS1066: Ambient enum elements can only have integer literal initializers.
+        c = b,
+        ~
+!!! error TS1066: Ambient enum elements can only have integer literal initializers.
+        d = (c) + 1,
+        ~
+!!! error TS1066: Ambient enum elements can only have integer literal initializers.
+        e = 10 << 2 * 8,
+        ~
+!!! error TS1066: Ambient enum elements can only have integer literal initializers.
+    }

tests/baselines/reference/ambientEnumDeclaration1.js

@@ -0,0 +1,13 @@
+//// [ambientEnumDeclaration1.ts]
+// In ambient enum declarations, all values specified in enum member declarations must be classified as constant enum expressions.
+
+declare enum E {
+    a = 10,
+    b = 10 + 1,
+    c = b,
+    d = (c) + 1,
+    e = 10 << 2 * 8,
+}
+
+//// [ambientEnumDeclaration1.js]
+// In ambient enum declarations, all values specified in enum member declarations must be classified as constant enum expressions.

tests/baselines/reference/ambientEnumDeclaration2.js

@@ -0,0 +1,17 @@
+//// [ambientEnumDeclaration2.ts]
+// In ambient enum declarations that specify no const modifier, enum member declarations
+// that omit a value are considered computed members (as opposed to having auto- incremented values assigned).
+
+declare enum E {
+    a, // E.a
+    b, // E.b
+}
+
+declare const enum E1 {
+    a, // E.a = 0
+    b, // E.b = 1
+}
+
+//// [ambientEnumDeclaration2.js]
+// In ambient enum declarations that specify no const modifier, enum member declarations
+// that omit a value are considered computed members (as opposed to having auto- incremented values assigned).

tests/baselines/reference/ambientEnumDeclaration2.symbols

@@ -0,0 +1,23 @@
+=== tests/cases/conformance/ambient/ambientEnumDeclaration2.ts ===
+// In ambient enum declarations that specify no const modifier, enum member declarations
+// that omit a value are considered computed members (as opposed to having auto- incremented values assigned).
+
+declare enum E {
+>E : Symbol(E, Decl(ambientEnumDeclaration2.ts, 0, 0))
+
+    a, // E.a
+>a : Symbol(E.a, Decl(ambientEnumDeclaration2.ts, 3, 16))
+
+    b, // E.b
+>b : Symbol(E.b, Decl(ambientEnumDeclaration2.ts, 4, 6))
+}
+
+declare const enum E1 {
+>E1 : Symbol(E1, Decl(ambientEnumDeclaration2.ts, 6, 1))
+
+    a, // E.a = 0
+>a : Symbol(E1.a, Decl(ambientEnumDeclaration2.ts, 8, 23))
+
+    b, // E.b = 1
+>b : Symbol(E1.b, Decl(ambientEnumDeclaration2.ts, 9, 6))
+}

tests/baselines/reference/ambientEnumDeclaration2.types

@@ -0,0 +1,23 @@
+=== tests/cases/conformance/ambient/ambientEnumDeclaration2.ts ===
+// In ambient enum declarations that specify no const modifier, enum member declarations
+// that omit a value are considered computed members (as opposed to having auto- incremented values assigned).
+
+declare enum E {
+>E : E
+
+    a, // E.a
+>a : E
+
+    b, // E.b
+>b : E
+}
+
+declare const enum E1 {
+>E1 : E1
+
+    a, // E.a = 0
+>a : E1
+
+    b, // E.b = 1
+>b : E1
+}

tests/baselines/reference/constEnum1.js

@@ -0,0 +1,34 @@
+//// [constEnum1.ts]
+
+// An enum declaration that specifies a const modifier is a constant enum declaration.
+// In a constant enum declaration, all members must have constant values and
+// it is an error for a member declaration to specify an expression that isn't classified as a constant enum expression.
+
+const enum E {
+    a = 10,
+    b = a,
+    c = (a+1),
+    e,
+    d = ~e,
+    f = a << 2 >> 1,
+    g = a << 2 >>> 1,
+    h = a | b
+}
+
+//// [constEnum1.js]
+// An enum declaration that specifies a const modifier is a constant enum declaration.
+// In a constant enum declaration, all members must have constant values and
+// it is an error for a member declaration to specify an expression that isn't classified as a constant enum expression.
+
+
+//// [constEnum1.d.ts]
+declare const enum E {
+    a = 10,
+    b = 10,
+    c = 11,
+    e = 12,
+    d = -13,
+    f = 20,
+    g = 20,
+    h = 10,
+}

tests/baselines/reference/constEnum1.symbols

@@ -0,0 +1,40 @@
+=== tests/cases/conformance/constEnums/constEnum1.ts ===
+
+// An enum declaration that specifies a const modifier is a constant enum declaration.
+// In a constant enum declaration, all members must have constant values and
+// it is an error for a member declaration to specify an expression that isn't classified as a constant enum expression.
+
+const enum E {
+>E : Symbol(E, Decl(constEnum1.ts, 0, 0))
+
+    a = 10,
+>a : Symbol(E.a, Decl(constEnum1.ts, 5, 14))
+
+    b = a,
+>b : Symbol(E.b, Decl(constEnum1.ts, 6, 11))
+>a : Symbol(E.a, Decl(constEnum1.ts, 5, 14))
+
+    c = (a+1),
+>c : Symbol(E.c, Decl(constEnum1.ts, 7, 10))
+>a : Symbol(E.a, Decl(constEnum1.ts, 5, 14))
+
+    e,
+>e : Symbol(E.e, Decl(constEnum1.ts, 8, 14))
+
+    d = ~e,
+>d : Symbol(E.d, Decl(constEnum1.ts, 9, 6))
+>e : Symbol(E.e, Decl(constEnum1.ts, 8, 14))
+
+    f = a << 2 >> 1,
+>f : Symbol(E.f, Decl(constEnum1.ts, 10, 11))
+>a : Symbol(E.a, Decl(constEnum1.ts, 5, 14))
+
+    g = a << 2 >>> 1,
+>g : Symbol(E.g, Decl(constEnum1.ts, 11, 20))
+>a : Symbol(E.a, Decl(constEnum1.ts, 5, 14))
+
+    h = a | b
+>h : Symbol(E.h, Decl(constEnum1.ts, 12, 21))
+>a : Symbol(E.a, Decl(constEnum1.ts, 5, 14))
+>b : Symbol(E.b, Decl(constEnum1.ts, 6, 11))
+}

tests/baselines/reference/constEnum1.types

@@ -0,0 +1,54 @@
+=== tests/cases/conformance/constEnums/constEnum1.ts ===
+
+// An enum declaration that specifies a const modifier is a constant enum declaration.
+// In a constant enum declaration, all members must have constant values and
+// it is an error for a member declaration to specify an expression that isn't classified as a constant enum expression.
+
+const enum E {
+>E : E
+
+    a = 10,
+>a : E
+>10 : number
+
+    b = a,
+>b : E
+>a : E
+
+    c = (a+1),
+>c : E
+>(a+1) : number
+>a+1 : number
+>a : E
+>1 : number
+
+    e,
+>e : E
+
+    d = ~e,
+>d : E
+>~e : number
+>e : E
+
+    f = a << 2 >> 1,
+>f : E
+>a << 2 >> 1 : number
+>a << 2 : number
+>a : E
+>2 : number
+>1 : number
+
+    g = a << 2 >>> 1,
+>g : E
+>a << 2 >>> 1 : number
+>a << 2 : number
+>a : E
+>2 : number
+>1 : number
+
+    h = a | b
+>h : E
+>a | b : number
+>a : E
+>b : E
+}

tests/baselines/reference/constEnum2.errors.txt

@@ -0,0 +1,29 @@
+tests/cases/conformance/constEnums/constEnum2.ts(11,9): error TS2474: In 'const' enum declarations member initializer must be constant expression.
+tests/cases/conformance/constEnums/constEnum2.ts(12,9): error TS2474: In 'const' enum declarations member initializer must be constant expression.
+tests/cases/conformance/constEnums/constEnum2.ts(13,5): error TS1005: ',' expected.
+tests/cases/conformance/constEnums/constEnum2.ts(13,9): error TS2474: In 'const' enum declarations member initializer must be constant expression.
+
+
+==== tests/cases/conformance/constEnums/constEnum2.ts (4 errors) ====
+    
+    // An enum declaration that specifies a const modifier is a constant enum declaration.
+    // In a constant enum declaration, all members must have constant values and
+    // it is an error for a member declaration to specify an expression that isn't classified as a constant enum expression.
+    
+    // Error : not a constant enum expression
+    
+    const CONST = 9000 % 2;
+    const enum D {
+        d = 10,
+        e = 199 * Math.floor(Math.random() * 1000),
+            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+!!! error TS2474: In 'const' enum declarations member initializer must be constant expression.
+        f = d - (100 * Math.floor(Math.random() % 8))
+            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+!!! error TS2474: In 'const' enum declarations member initializer must be constant expression.
+        g = CONST,
+        ~
+!!! error TS1005: ',' expected.
+            ~~~~~
+!!! error TS2474: In 'const' enum declarations member initializer must be constant expression.
+    }

tests/baselines/reference/constEnum2.js

@@ -0,0 +1,32 @@
+//// [constEnum2.ts]
+
+// An enum declaration that specifies a const modifier is a constant enum declaration.
+// In a constant enum declaration, all members must have constant values and
+// it is an error for a member declaration to specify an expression that isn't classified as a constant enum expression.
+
+// Error : not a constant enum expression
+
+const CONST = 9000 % 2;
+const enum D {
+    d = 10,
+    e = 199 * Math.floor(Math.random() * 1000),
+    f = d - (100 * Math.floor(Math.random() % 8))
+    g = CONST,
+}
+
+//// [constEnum2.js]
+// An enum declaration that specifies a const modifier is a constant enum declaration.
+// In a constant enum declaration, all members must have constant values and
+// it is an error for a member declaration to specify an expression that isn't classified as a constant enum expression.
+// Error : not a constant enum expression
+var CONST = 9000 % 2;
+
+
+//// [constEnum2.d.ts]
+declare const CONST: number;
+declare const enum D {
+    d = 10,
+    e,
+    f,
+    g,
+}

tests/baselines/reference/constEnumPropertyAccess1.js

@@ -0,0 +1,67 @@
+//// [constEnumPropertyAccess1.ts]
+
+// constant enum declarations are completely erased in the emitted JavaScript code.
+// it is an error to reference a constant enum object in any other context
+// than a property access that selects one of the enum's members
+
+const enum G {
+    A = 1,
+    B = 2,
+    C = A + B,
+    D = A * 2
+}
+
+var o: {
+    [idx: number]: boolean
+} = {
+        1: true
+    };
+
+var a = G.A;
+var a1 = G["A"];
+var g = o[G.A];
+
+class C {
+    [G.A]() { }
+    get [G.B]() {
+        return true;
+    }
+    set [G.B](x: number) { }
+}
+
+
+
+//// [constEnumPropertyAccess1.js]
+// constant enum declarations are completely erased in the emitted JavaScript code.
+// it is an error to reference a constant enum object in any other context
+// than a property access that selects one of the enum's members
+var o = {
+    1: true
+};
+var a = 1 /* A */;
+var a1 = 1 /* "A" */;
+var g = o[1 /* A */];
+class C {
+    [1 /* A */]() { }
+    get [2 /* B */]() {
+        return true;
+    }
+    set [2 /* B */](x) { }
+}
+
+
+//// [constEnumPropertyAccess1.d.ts]
+declare const enum G {
+    A = 1,
+    B = 2,
+    C = 3,
+    D = 2,
+}
+declare var o: {
+    [idx: number]: boolean;
+};
+declare var a: G;
+declare var a1: G;
+declare var g: boolean;
+declare class C {
+}

tests/baselines/reference/constEnumPropertyAccess1.symbols

@@ -0,0 +1,76 @@
+=== tests/cases/conformance/constEnums/constEnumPropertyAccess1.ts ===
+
+// constant enum declarations are completely erased in the emitted JavaScript code.
+// it is an error to reference a constant enum object in any other context
+// than a property access that selects one of the enum's members
+
+const enum G {
+>G : Symbol(G, Decl(constEnumPropertyAccess1.ts, 0, 0))
+
+    A = 1,
+>A : Symbol(G.A, Decl(constEnumPropertyAccess1.ts, 5, 14))
+
+    B = 2,
+>B : Symbol(G.B, Decl(constEnumPropertyAccess1.ts, 6, 10))
+
+    C = A + B,
+>C : Symbol(G.C, Decl(constEnumPropertyAccess1.ts, 7, 10))
+>A : Symbol(G.A, Decl(constEnumPropertyAccess1.ts, 5, 14))
+>B : Symbol(G.B, Decl(constEnumPropertyAccess1.ts, 6, 10))
+
+    D = A * 2
+>D : Symbol(G.D, Decl(constEnumPropertyAccess1.ts, 8, 14))
+>A : Symbol(G.A, Decl(constEnumPropertyAccess1.ts, 5, 14))
+}
+
+var o: {
+>o : Symbol(o, Decl(constEnumPropertyAccess1.ts, 12, 3))
+
+    [idx: number]: boolean
+>idx : Symbol(idx, Decl(constEnumPropertyAccess1.ts, 13, 5))
+
+} = {
+        1: true
+    };
+
+var a = G.A;
+>a : Symbol(a, Decl(constEnumPropertyAccess1.ts, 18, 3))
+>G.A : Symbol(G.A, Decl(constEnumPropertyAccess1.ts, 5, 14))
+>G : Symbol(G, Decl(constEnumPropertyAccess1.ts, 0, 0))
+>A : Symbol(G.A, Decl(constEnumPropertyAccess1.ts, 5, 14))
+
+var a1 = G["A"];
+>a1 : Symbol(a1, Decl(constEnumPropertyAccess1.ts, 19, 3))
+>G : Symbol(G, Decl(constEnumPropertyAccess1.ts, 0, 0))
+>"A" : Symbol(G.A, Decl(constEnumPropertyAccess1.ts, 5, 14))
+
+var g = o[G.A];
+>g : Symbol(g, Decl(constEnumPropertyAccess1.ts, 20, 3))
+>o : Symbol(o, Decl(constEnumPropertyAccess1.ts, 12, 3))
+>G.A : Symbol(G.A, Decl(constEnumPropertyAccess1.ts, 5, 14))
+>G : Symbol(G, Decl(constEnumPropertyAccess1.ts, 0, 0))
+>A : Symbol(G.A, Decl(constEnumPropertyAccess1.ts, 5, 14))
+
+class C {
+>C : Symbol(C, Decl(constEnumPropertyAccess1.ts, 20, 15))
+
+    [G.A]() { }
+>G.A : Symbol(G.A, Decl(constEnumPropertyAccess1.ts, 5, 14))
+>G : Symbol(G, Decl(constEnumPropertyAccess1.ts, 0, 0))
+>A : Symbol(G.A, Decl(constEnumPropertyAccess1.ts, 5, 14))
+
+    get [G.B]() {
+>G.B : Symbol(G.B, Decl(constEnumPropertyAccess1.ts, 6, 10))
+>G : Symbol(G, Decl(constEnumPropertyAccess1.ts, 0, 0))
+>B : Symbol(G.B, Decl(constEnumPropertyAccess1.ts, 6, 10))
+
+        return true;
+    }
+    set [G.B](x: number) { }
+>G.B : Symbol(G.B, Decl(constEnumPropertyAccess1.ts, 6, 10))
+>G : Symbol(G, Decl(constEnumPropertyAccess1.ts, 0, 0))
+>B : Symbol(G.B, Decl(constEnumPropertyAccess1.ts, 6, 10))
+>x : Symbol(x, Decl(constEnumPropertyAccess1.ts, 27, 14))
+}
+
+

tests/baselines/reference/constEnumPropertyAccess1.types

@@ -0,0 +1,88 @@
+=== tests/cases/conformance/constEnums/constEnumPropertyAccess1.ts ===
+
+// constant enum declarations are completely erased in the emitted JavaScript code.
+// it is an error to reference a constant enum object in any other context
+// than a property access that selects one of the enum's members
+
+const enum G {
+>G : G
+
+    A = 1,
+>A : G
+>1 : number
+
+    B = 2,
+>B : G
+>2 : number
+
+    C = A + B,
+>C : G
+>A + B : number
+>A : G
+>B : G
+
+    D = A * 2
+>D : G
+>A * 2 : number
+>A : G
+>2 : number
+}
+
+var o: {
+>o : { [idx: number]: boolean; }
+
+    [idx: number]: boolean
+>idx : number
+
+} = {
+>{        1: true    } : { [x: number]: boolean; 1: boolean; }
+
+        1: true
+>true : boolean
+
+    };
+
+var a = G.A;
+>a : G
+>G.A : G
+>G : typeof G
+>A : G
+
+var a1 = G["A"];
+>a1 : G
+>G["A"] : G
+>G : typeof G
+>"A" : string
+
+var g = o[G.A];
+>g : boolean
+>o[G.A] : boolean
+>o : { [idx: number]: boolean; }
+>G.A : G
+>G : typeof G
+>A : G
+
+class C {
+>C : C
+
+    [G.A]() { }
+>G.A : G
+>G : typeof G
+>A : G
+
+    get [G.B]() {
+>G.B : G
+>G : typeof G
+>B : G
+
+        return true;
+>true : boolean
+    }
+    set [G.B](x: number) { }
+>G.B : G
+>G : typeof G
+>B : G
+>x : number
+}
+
+

tests/baselines/reference/constEnumPropertyAccess2.errors.txt

@@ -0,0 +1,35 @@
+tests/cases/conformance/constEnums/constEnumPropertyAccess2.ts(14,9): error TS2475: 'const' enums can only be used in property or index access expressions or the right hand side of an import declaration or export assignment.
+tests/cases/conformance/constEnums/constEnumPropertyAccess2.ts(15,12): error TS2476: A const enum member can only be accessed using a string literal.
+tests/cases/conformance/constEnums/constEnumPropertyAccess2.ts(17,1): error TS2322: Type 'string' is not assignable to type 'G'.
+tests/cases/conformance/constEnums/constEnumPropertyAccess2.ts(19,1): error TS2364: Invalid left-hand side of assignment expression.
+
+
+==== tests/cases/conformance/constEnums/constEnumPropertyAccess2.ts (4 errors) ====
+    
+    // constant enum declarations are completely erased in the emitted JavaScript code.
+    // it is an error to reference a constant enum object in any other context
+    // than a property access that selects one of the enum's members
+    
+    const enum G {
+        A = 1,
+        B = 2,
+        C = A + B,
+        D = A * 2
+    }
+    
+    // Error from referring constant enum in any other context than a property access
+    var z = G;
+            ~
+!!! error TS2475: 'const' enums can only be used in property or index access expressions or the right hand side of an import declaration or export assignment.
+    var z1 = G[G.A];
+               ~~~
+!!! error TS2476: A const enum member can only be accessed using a string literal.
+    var g: G;
+    g = "string";
+    ~
+!!! error TS2322: Type 'string' is not assignable to type 'G'.
+    function foo(x: G) { }
+    G.B = 3;
+    ~~~
+!!! error TS2364: Invalid left-hand side of assignment expression.
+    

tests/baselines/reference/constEnumPropertyAccess2.js

@@ -0,0 +1,46 @@
+//// [constEnumPropertyAccess2.ts]
+
+// constant enum declarations are completely erased in the emitted JavaScript code.
+// it is an error to reference a constant enum object in any other context
+// than a property access that selects one of the enum's members
+
+const enum G {
+    A = 1,
+    B = 2,
+    C = A + B,
+    D = A * 2
+}
+
+// Error from referring constant enum in any other context than a property access
+var z = G;
+var z1 = G[G.A];
+var g: G;
+g = "string";
+function foo(x: G) { }
+G.B = 3;
+
+
+//// [constEnumPropertyAccess2.js]
+// constant enum declarations are completely erased in the emitted JavaScript code.
+// it is an error to reference a constant enum object in any other context
+// than a property access that selects one of the enum's members
+// Error from referring constant enum in any other context than a property access
+var z = G;
+var z1 = G[1 /* A */];
+var g;
+g = "string";
+function foo(x) { }
+2 /* B */ = 3;
+
+
+//// [constEnumPropertyAccess2.d.ts]
+declare const enum G {
+    A = 1,
+    B = 2,
+    C = 3,
+    D = 2,
+}
+declare var z: typeof G;
+declare var z1: any;
+declare var g: G;
+declare function foo(x: G): void;

tests/cases/conformance/ambient/ambientEnumDeclaration1.ts

@@ -0,0 +1,9 @@
+// In ambient enum declarations, all values specified in enum member declarations must be classified as constant enum expressions.
+
+declare enum E {
+    a = 10,
+    b = 10 + 1,
+    c = b,
+    d = (c) + 1,
+    e = 10 << 2 * 8,
+}

tests/cases/conformance/ambient/ambientEnumDeclaration2.ts

@@ -0,0 +1,12 @@
+// In ambient enum declarations that specify no const modifier, enum member declarations
+// that omit a value are considered computed members (as opposed to having auto- incremented values assigned).
+
+declare enum E {
+    a, // E.a
+    b, // E.b
+}
+
+declare const enum E1 {
+    a, // E.a = 0
+    b, // E.b = 1
+}

tests/cases/conformance/constEnums/constEnum1.ts

@@ -0,0 +1,16 @@
+// @declaration: true
+
+// An enum declaration that specifies a const modifier is a constant enum declaration.
+// In a constant enum declaration, all members must have constant values and
+// it is an error for a member declaration to specify an expression that isn't classified as a constant enum expression.
+
+const enum E {
+    a = 10,
+    b = a,
+    c = (a+1),
+    e,
+    d = ~e,
+    f = a << 2 >> 1,
+    g = a << 2 >>> 1,
+    h = a | b
+}

tests/cases/conformance/constEnums/constEnum2.ts

@@ -0,0 +1,15 @@
+// @declaration: true
+
+// An enum declaration that specifies a const modifier is a constant enum declaration.
+// In a constant enum declaration, all members must have constant values and
+// it is an error for a member declaration to specify an expression that isn't classified as a constant enum expression.
+
+// Error : not a constant enum expression
+
+const CONST = 9000 % 2;
+const enum D {
+    d = 10,
+    e = 199 * Math.floor(Math.random() * 1000),
+    f = d - (100 * Math.floor(Math.random() % 8))
+    g = CONST,
+}

tests/cases/conformance/constEnums/constEnumPropertyAccess1.ts

@@ -0,0 +1,32 @@
+// @declaration: true
+// @target: es6
+
+// constant enum declarations are completely erased in the emitted JavaScript code.
+// it is an error to reference a constant enum object in any other context
+// than a property access that selects one of the enum's members
+
+const enum G {
+    A = 1,
+    B = 2,
+    C = A + B,
+    D = A * 2
+}
+
+var o: {
+    [idx: number]: boolean
+} = {
+        1: true
+    };
+
+var a = G.A;
+var a1 = G["A"];
+var g = o[G.A];
+
+class C {
+    [G.A]() { }
+    get [G.B]() {
+        return true;
+    }
+    set [G.B](x: number) { }
+}
+

tests/cases/conformance/constEnums/constEnumPropertyAccess2.ts

@@ -0,0 +1,20 @@
+// @declaration: true
+
+// constant enum declarations are completely erased in the emitted JavaScript code.
+// it is an error to reference a constant enum object in any other context
+// than a property access that selects one of the enum's members
+
+const enum G {
+    A = 1,
+    B = 2,
+    C = A + B,
+    D = A * 2
+}
+
+// Error from referring constant enum in any other context than a property access
+var z = G;
+var z1 = G[G.A];
+var g: G;
+g = "string";
+function foo(x: G) { }
+G.B = 3;