diff --git a/.travis.yml b/.travis.yml
new file mode 100644
index 00000000000..9a61f6bd7c5
--- /dev/null
+++ b/.travis.yml
@@ -0,0 +1,3 @@
+language: node_js
+node_js:
+  - "0.10"
\ No newline at end of file
diff --git a/Jakefile b/Jakefile
index 37242552526..a25fb8a9b0d 100644
--- a/Jakefile
+++ b/Jakefile
@@ -17,6 +17,9 @@ var LKGDirectory = "bin/";
 var copyright = "CopyrightNotice.txt";
 var thirdParty = "ThirdPartyNoticeText.txt";
 
+// add node_modules to path so we don't need global modules, prefer the modules by adding them first
+process.env.path = path.resolve("./node_modules/.bin/") + path.delimiter + process.env.path;
+
 var compilerSources = [
     "core.ts",
     "sys.ts",
diff --git a/package.json b/package.json
index 809ba9074c4..71dba4fbefd 100644
--- a/package.json
+++ b/package.json
@@ -37,5 +37,8 @@
 		"mocha" : "latest",
 		"chai" : "latest",
 		"browserify" : "latest"
+	},
+	"scripts": {
+		"test": "jake runtests"
 	}
 }
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index ffe79d7b48c..3c994fc3fe4 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -2978,6 +2978,33 @@ module ts {
             return type;
         }
 
+        function forEachMatchingParameterType(source: Signature, target: Signature, callback: (s: Type, t: Type) => void) {
+            var sourceMax = source.parameters.length;
+            var targetMax = target.parameters.length;
+            var count: number;
+            if (source.hasRestParameter && target.hasRestParameter) {
+                count = sourceMax > targetMax ? sourceMax : targetMax;
+                sourceMax--;
+                targetMax--;
+            }
+            else if (source.hasRestParameter) {
+                sourceMax--;
+                count = targetMax;
+            }
+            else if (target.hasRestParameter) {
+                targetMax--;
+                count = sourceMax;
+            }
+            else {
+                count = sourceMax < targetMax ? sourceMax : targetMax;
+            }
+            for (var i = 0; i < count; i++) {
+                var s = i < sourceMax ? getTypeOfSymbol(source.parameters[i]) : getRestTypeOfSignature(source);
+                var t = i < targetMax ? getTypeOfSymbol(target.parameters[i]) : getRestTypeOfSignature(target);
+                callback(s, t);
+            }
+        }
+
         function createInferenceContext(typeParameters: TypeParameter[]): InferenceContext {
             var inferences: Type[][] = [];
             for (var i = 0; i < typeParameters.length; i++) inferences.push([]);
@@ -3048,8 +3075,9 @@ module ts {
                         inferFromProperties(source, target);
                         inferFromSignatures(source, target, SignatureKind.Call);
                         inferFromSignatures(source, target, SignatureKind.Construct);
-                        inferFromIndexTypes(source, target, IndexKind.String);
-                        inferFromIndexTypes(source, target, IndexKind.Number);
+                        inferFromIndexTypes(source, target, IndexKind.String, IndexKind.String);
+                        inferFromIndexTypes(source, target, IndexKind.Number, IndexKind.Number);
+                        inferFromIndexTypes(source, target, IndexKind.String, IndexKind.Number);
                         depth--;
                     }
                 }
@@ -3073,42 +3101,19 @@ module ts {
                 var targetLen = targetSignatures.length;
                 var len = sourceLen < targetLen ? sourceLen : targetLen;
                 for (var i = 0; i < len; i++) {
-                    inferFromParameters(getErasedSignature(sourceSignatures[sourceLen - len + i]), getErasedSignature(targetSignatures[targetLen - len + i]));
+                    inferFromSignature(getErasedSignature(sourceSignatures[sourceLen - len + i]), getErasedSignature(targetSignatures[targetLen - len + i]));
                 }
             }
 
-            function inferFromParameters(source: Signature, target: Signature) {
-                var sourceMax = source.parameters.length;
-                var targetMax = target.parameters.length;
-                var checkCount: number;
-                if (!source.hasRestParameter && !target.hasRestParameter) {
-                    checkCount = sourceMax < targetMax ? sourceMax : targetMax;
-                }
-                else if (source.hasRestParameter) {
-                    sourceMax--;
-                    checkCount = targetMax;
-                }
-                else if (target.hasRestParameter) {
-                    targetMax--;
-                    checkCount = sourceMax;
-                }
-                else {
-                    checkCount = sourceMax > targetMax ? sourceMax : targetMax;
-                    sourceMax--;
-                    targetMax--;
-                }
-                for (var i = 0; i < checkCount; i++) {
-                    var s = i < sourceMax ? getTypeOfSymbol(source.parameters[i]) : getRestTypeOfSignature(source);
-                    var t = i < targetMax ? getTypeOfSymbol(target.parameters[i]) : getRestTypeOfSignature(target);
-                    inferFromTypes(s, t);
-                }
+            function inferFromSignature(source: Signature, target: Signature) {
+                forEachMatchingParameterType(source, target, inferFromTypes);
                 inferFromTypes(getReturnTypeOfSignature(source), getReturnTypeOfSignature(target));
             }
 
-            function inferFromIndexTypes(source: Type, target: Type, kind: IndexKind) {
-                var targetIndexType = getIndexTypeOfType(target, kind);
+            function inferFromIndexTypes(source: Type, target: Type, sourceKind: IndexKind, targetKind: IndexKind) {
+                var targetIndexType = getIndexTypeOfType(target, targetKind);
                 if (targetIndexType) {
-                    var sourceIndexType = getIndexTypeOfType(source, kind);
+                    var sourceIndexType = getIndexTypeOfType(source, sourceKind);
                     if (sourceIndexType) {
                         inferFromTypes(sourceIndexType, targetIndexType);
                     }
@@ -3655,6 +3660,41 @@ module ts {
             return result;
         }
 
+        // If type has a single call signature and no other members, return that signature. Otherwise, return undefined.
+        function getSingleCallSignature(type: Type): Signature {
+            if (type.flags & TypeFlags.ObjectType) {
+                var resolved = resolveObjectTypeMembers(<ObjectType>type);
+                if (resolved.callSignatures.length === 1 && resolved.constructSignatures.length === 0 &&
+                    resolved.properties.length === 0 && !resolved.stringIndexType && !resolved.numberIndexType) {
+                    return resolved.callSignatures[0];
+                }
+            }
+            return undefined;
+        }
+
+        // Instantiate a generic signature in the context of a non-generic signature (section 3.8.5 in TypeScript spec)
+        function instantiateSignatureInContextOf(signature: Signature, contextualSignature: Signature, contextualMapper: TypeMapper): Signature {
+            var context = createInferenceContext(signature.typeParameters);
+            forEachMatchingParameterType(contextualSignature, signature, (source, target) => {
+                // Type parameters from outer context referenced by source type are fixed by instantiation of the source type
+                inferTypes(context, instantiateType(source, contextualMapper), target);
+            });
+            return getSignatureInstantiation(signature, getInferredTypes(context));
+        }
+
+        // Inferentially type an expression by a contextual parameter type (section 4.12.2 in TypeScript spec)
+        function inferentiallyTypeExpession(expr: Expression, contextualType: Type, contextualMapper: TypeMapper): Type {
+            var type = checkExpression(expr, contextualType, contextualMapper);
+            var signature = getSingleCallSignature(type);
+            if (signature && signature.typeParameters) {
+                var contextualSignature = getSingleCallSignature(contextualType);
+                if (contextualSignature && !contextualSignature.typeParameters) {
+                    type = getOrCreateTypeFromSignature(instantiateSignatureInContextOf(signature, contextualSignature, contextualMapper));
+                }
+            }
+            return type;
+        }
+
         function inferTypeArguments(signature: Signature, args: Expression[], excludeArgument?: boolean[]): Type[] {
             var typeParameters = signature.typeParameters;
             var context = createInferenceContext(typeParameters);
@@ -3663,7 +3703,7 @@ module ts {
             for (var i = 0; i < args.length; i++) {
                 if (!excludeArgument || excludeArgument[i] === undefined) {
                     var parameterType = getTypeAtPosition(signature, i);
-                    inferTypes(context, checkExpression(args[i], parameterType, mapper), parameterType);
+                    inferTypes(context, inferentiallyTypeExpession(args[i], parameterType, mapper), parameterType);
                 }
             }
             // Next, infer from those context sensitive arguments that are no longer excluded
@@ -3671,7 +3711,7 @@ module ts {
                 for (var i = 0; i < args.length; i++) {
                     if (excludeArgument[i] === false) {
                         var parameterType = getTypeAtPosition(signature, i);
-                        inferTypes(context, checkExpression(args[i], parameterType, mapper), parameterType);
+                        inferTypes(context, inferentiallyTypeExpession(args[i], parameterType, mapper), parameterType);
                     }
                 }
             }
@@ -3932,12 +3972,10 @@ module ts {
             }
 
             // Aggregate the types of expressions within all the return statements.
-            var types: Type[] = [];
-            checkAndAggregateReturnExpressionTypes(func.body);
+            var types = checkAndAggregateReturnExpressionTypes(<Block>func.body, contextualType, contextualMapper);
 
             // Try to return the best common type if we have any return expressions.
-            if (types.length) {
-
+            if (types.length > 0) {
                 var commonType = getBestCommonType(types, /*contextualType:*/ undefined, /*candidatesOnly:*/ true);
                 if (!commonType) {
                     error(func, Diagnostics.No_best_common_type_exists_among_return_expressions);
@@ -3963,16 +4001,18 @@ module ts {
             }
 
             return voidType;
+        }
 
-            function checkAndAggregateReturnExpressionTypes(node: Node) {
+        // WARNING: This has the same semantics as the forEach family of functions,
+        //          in that traversal terminates in the event that 'visitor' supplies a truthy value.
+        function forEachReturnStatement<T>(body: Block, visitor: (stmt: ReturnStatement) => T): T {
+
+            return traverse(body);
+
+            function traverse(node: Node): T {
                 switch (node.kind) {
                     case SyntaxKind.ReturnStatement:
-                        var expr = (<ReturnStatement>node).expression;
-                        if (expr) {
-                            var type = checkAndMarkExpression(expr, contextualType, contextualMapper);
-                            if (!contains(types, type)) types.push(type);
-                        }
-                        break;
+                        return visitor(node);
                     case SyntaxKind.Block:
                     case SyntaxKind.FunctionBlock:
                     case SyntaxKind.IfStatement:
@@ -3989,15 +4029,77 @@ module ts {
                     case SyntaxKind.TryBlock:
                     case SyntaxKind.CatchBlock:
                     case SyntaxKind.FinallyBlock:
-                        forEachChild(node, checkAndAggregateReturnExpressionTypes);
-                        break;
+                        return forEachChild(node, traverse);
                 }
             }
         }
 
+        /// Returns a set of types relating to every return expression relating to a function block.
+        function checkAndAggregateReturnExpressionTypes(body: Block, contextualType?: Type, contextualMapper?: TypeMapper): Type[] {
+            var aggregatedTypes: Type[] = [];
+
+            forEachReturnStatement(body, returnStatement => {
+                var expr = returnStatement.expression;
+                if (expr) {
+                    var type = checkAndMarkExpression(expr, contextualType, contextualMapper);
+                    if (!contains(aggregatedTypes, type)) {
+                        aggregatedTypes.push(type);
+                    }
+                }
+            });
+
+            return aggregatedTypes;
+        }
+
+        function bodyContainsAReturnStatement(funcBody: Block) {
+            return forEachReturnStatement(funcBody, returnStatement => {
+                return true;
+            });
+        }
+
+        function bodyContainsSingleThrowStatement(body: Block) {
+            return (body.statements.length === 1) && (body.statements[0].kind === SyntaxKind.ThrowStatement)
+        }
+
+        // TypeScript Specification 1.0 (6.3) - July 2014
+        // An explicitly typed function whose return type isn't the Void or the Any type
+        // must have at least one return statement somewhere in its body.
+        // An exception to this rule is if the function implementation consists of a single 'throw' statement.
+        function checkIfNonVoidFunctionHasReturnExpressionsOrSingleThrowStatment(func: FunctionDeclaration, returnType: Type): void {
+            // Functions that return 'void' or 'any' don't need any return expressions.
+            if (returnType === voidType || returnType === anyType) {
+                return;
+            }
+
+            // If all we have is a function signature, or an arrow function with an expression body, then there is nothing to check.
+            if (!func.body || func.body.kind !== SyntaxKind.FunctionBlock) {
+                return;
+            }
+
+            var bodyBlock = <Block>func.body;
+
+            // Ensure the body has at least one return expression.
+            if (bodyContainsAReturnStatement(bodyBlock)) {
+                return;
+            }
+
+            // If there are no return expressions, then we need to check if
+            // the function body consists solely of a throw statement;
+            // this is to make an exception for unimplemented functions.
+            if (bodyContainsSingleThrowStatement(bodyBlock)) {
+                return;
+            }
+
+            // This function does not conform to the specification.
+            error(func.type, Diagnostics.A_function_whose_declared_type_is_neither_void_nor_any_must_return_a_value_or_consist_of_a_single_throw_statement);
+        }
+
         function checkFunctionExpression(node: FunctionExpression, contextualType?: Type, contextualMapper?: TypeMapper): Type {
             // The identityMapper object is used to indicate that function expressions are wildcards
-            if (contextualMapper === identityMapper) return anyFunctionType;
+            if (contextualMapper === identityMapper) {
+                return anyFunctionType;
+            }
+
             var type = getTypeOfSymbol(node.symbol);
             var links = getNodeLinks(node);
 
@@ -4015,6 +4117,9 @@ module ts {
                             signature.resolvedReturnType = returnType;
                         }
                     }
+                    else {
+                        checkIfNonVoidFunctionHasReturnExpressionsOrSingleThrowStatment(node, getTypeFromTypeNode(node.type));
+                    }
                 }
                 checkSignatureDeclaration(node);
                 if (node.body.kind === SyntaxKind.FunctionBlock) {
@@ -4587,28 +4692,9 @@ module ts {
         }
 
         function checkAccessorDeclaration(node: AccessorDeclaration) {
-            function checkGetterContainsSingleThrowStatement(node: AccessorDeclaration): boolean {
-                var block = <Block>node.body;
-                return block.statements.length === 1 && block.statements[0].kind === SyntaxKind.ThrowStatement;
-            }
-
-            function checkGetterReturnsValue(n: Node): boolean {
-                switch (n.kind) {
-                    case SyntaxKind.ReturnStatement:
-                        return true;
-                    // do not dive into function-like things - return statements there don't count
-                    case SyntaxKind.FunctionExpression:
-                    case SyntaxKind.FunctionDeclaration:
-                    case SyntaxKind.ArrowFunction:
-                    case SyntaxKind.ObjectLiteral:
-                        return false;
-                    default:
-                        return forEachChild(n, checkGetterReturnsValue);
-                }
-            }            
             if (node.kind === SyntaxKind.GetAccessor) {
-                if (!isInAmbientContext(node) && node.body && !(checkGetterContainsSingleThrowStatement(node) || checkGetterReturnsValue(node))) {
-                    error(node.name, Diagnostics.Getters_must_return_a_value);
+                if (!isInAmbientContext(node) && node.body && !(bodyContainsAReturnStatement(<Block>node.body) || bodyContainsSingleThrowStatement(<Block>node.body))) {
+                    error(node.name, Diagnostics.A_get_accessor_must_return_a_value_or_consist_of_a_single_throw_statement);
                 }
             }
 
@@ -4837,8 +4923,6 @@ module ts {
                     }
                 }
             }
-
-            // TODO: Check at least one return statement in non-void/any function (except single throw)
         }
 
         function checkFunctionDeclaration(node: FunctionDeclaration) {
@@ -4850,7 +4934,11 @@ module ts {
             if (node === firstDeclaration) {
                 checkFunctionOrConstructorSymbol(symbol);
             }
+
             checkSourceElement(node.body);
+            if (node.type) {
+                checkIfNonVoidFunctionHasReturnExpressionsOrSingleThrowStatment(node, getTypeFromTypeNode(node.type));
+            }
 
             // If there is no body and no explicit return type, then report an error.
             if (program.getCompilerOptions().noImplicitAny && !node.body && !node.type) {
@@ -5255,7 +5343,7 @@ module ts {
                     // for interfaces property and indexer might be inherited from different bases
                     // check if any base class already has both property and indexer.
                     // check should be performed only if 'type' is the first type that brings property\indexer together
-                    var someBaseClassHasBothPropertyAndIndexer = forEach((<InterfaceType>type).baseTypes, (base) => getPropertyOfType(base, prop.name) && getIndexTypeOfType(base, indexKind));
+                    var someBaseClassHasBothPropertyAndIndexer = forEach((<InterfaceType>type).baseTypes, base => getPropertyOfType(base, prop.name) && getIndexTypeOfType(base, indexKind));
                     errorNode = someBaseClassHasBothPropertyAndIndexer ? undefined : type.symbol.declarations[0];
                 }
 
diff --git a/src/compiler/diagnosticInformationMap.generated.ts b/src/compiler/diagnosticInformationMap.generated.ts
index c2c422c64b6..8f58d9f3042 100644
--- a/src/compiler/diagnosticInformationMap.generated.ts
+++ b/src/compiler/diagnosticInformationMap.generated.ts
@@ -114,8 +114,9 @@ module ts {
         The_right_hand_side_of_a_for_in_statement_must_be_of_type_any_an_object_type_or_a_type_parameter: { code: 2117, category: DiagnosticCategory.Error, key: "The right-hand side of a 'for...in' statement must be of type 'any', an object type or a type parameter." },
         The_left_hand_side_of_an_in_expression_must_be_of_types_any_string_or_number: { code: 2118, category: DiagnosticCategory.Error, key: "The left-hand side of an 'in' expression must be of types 'any', 'string' or 'number'." },
         The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: { code: 2119, category: DiagnosticCategory.Error, key: "The right-hand side of an 'in' expression must be of type 'any', an object type or a type parameter" },
-        Getters_must_return_a_value: { code: 2126, category: DiagnosticCategory.Error, key: "Getters must return a value." },
+        A_get_accessor_must_return_a_value_or_consist_of_a_single_throw_statement: { code: 2126, category: DiagnosticCategory.Error, key: "A 'get' accessor must return a value or consist of a single 'throw' statement." },
         Getter_and_setter_accessors_do_not_agree_in_visibility: { code: 2127, category: DiagnosticCategory.Error, key: "Getter and setter accessors do not agree in visibility." },
+        A_function_whose_declared_type_is_neither_void_nor_any_must_return_a_value_or_consist_of_a_single_throw_statement: { code: 2131, category: DiagnosticCategory.Error, key: "A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement." },
         Untyped_function_calls_may_not_accept_type_arguments: { code: 2158, category: DiagnosticCategory.Error, key: "Untyped function calls may not accept type arguments." },
         The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: { code: 2120, category: DiagnosticCategory.Error, key: "The left-hand side of an 'instanceof' expression must be of type 'any', an object type or a type parameter." },
         The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_Function_interface_type: { code: 2121, category: DiagnosticCategory.Error, key: "The right-hand side of an 'instanceof' expression must be of type 'any' or of a type assignable to the 'Function' interface type." },
diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index ad5e89f2b38..b418ec7a404 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -449,7 +449,7 @@
         "category": "Error",
         "code": 2119
     },
-    "Getters must return a value.": {
+    "A 'get' accessor must return a value or consist of a single 'throw' statement.": {
         "category": "Error",
         "code": 2126
     },
@@ -457,6 +457,10 @@
         "category": "Error",
         "code": 2127
     },
+    "A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.": {
+        "category": "Error",
+        "code": 2131
+    },
     "Untyped function calls may not accept type arguments.": {
         "category": "Error",
         "code": 2158
diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index b132a7d13c1..0304586bbca 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -766,7 +766,7 @@ module ts {
             return false;
         }
 
-        // Parses a semicolon-delimited list of elements
+        // Parses a list of elements
         function parseList<T extends Node>(kind: ParsingContext, parseElement: () => T): NodeArray<T> {
             var saveParsingContext = parsingContext;
             parsingContext |= 1 << kind;
@@ -1070,7 +1070,7 @@ module ts {
             return finishNode(node);
         }
 
-        function checkIndexSignature(node: SignatureDeclaration, indexerStart: number, indexerLength: number): boolean {
+        function checkIndexSignature(node: SignatureDeclaration, indexerStart: number, indexerLength: number): void {
             var parameter = node.parameters[0];
             if (node.parameters.length !== 1) {
                 var arityDiagnostic = Diagnostics.An_index_signature_must_have_exactly_one_parameter
diff --git a/tests/baselines/reference/ParameterList5.errors.txt b/tests/baselines/reference/ParameterList5.errors.txt
index 37487b5c319..412fb71eb14 100644
--- a/tests/baselines/reference/ParameterList5.errors.txt
+++ b/tests/baselines/reference/ParameterList5.errors.txt
@@ -1,5 +1,7 @@
-==== tests/cases/compiler/ParameterList5.ts (2 errors) ====
+==== tests/cases/compiler/ParameterList5.ts (3 errors) ====
     function A(): (public B) => C {
+                  ~~~~~~~~~~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
                    ~~~~~~~~
 !!! A parameter property is only allowed in a constructor implementation.
                                 ~
diff --git a/tests/baselines/reference/ambientGetters.errors.txt b/tests/baselines/reference/ambientGetters.errors.txt
index 05c40581074..a8c913b66c7 100644
--- a/tests/baselines/reference/ambientGetters.errors.txt
+++ b/tests/baselines/reference/ambientGetters.errors.txt
@@ -1,9 +1,11 @@
-==== tests/cases/compiler/ambientGetters.ts (2 errors) ====
+==== tests/cases/compiler/ambientGetters.ts (3 errors) ====
     
     declare class A {
         get length() : number;
                              ~
 !!! '{' expected.
+                       ~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     }
     
     declare class B {
diff --git a/tests/baselines/reference/conflictingTypeAnnotatedVar.errors.txt b/tests/baselines/reference/conflictingTypeAnnotatedVar.errors.txt
index 85867f5e573..6bb45b67ee7 100644
--- a/tests/baselines/reference/conflictingTypeAnnotatedVar.errors.txt
+++ b/tests/baselines/reference/conflictingTypeAnnotatedVar.errors.txt
@@ -1,8 +1,12 @@
-==== tests/cases/compiler/conflictingTypeAnnotatedVar.ts (2 errors) ====
+==== tests/cases/compiler/conflictingTypeAnnotatedVar.ts (4 errors) ====
     var foo: string;
     function foo(): number { }
              ~~~
 !!! Duplicate identifier 'foo'.
+                    ~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     function foo(): number { }
              ~~~
-!!! Duplicate identifier 'foo'.
\ No newline at end of file
+!!! Duplicate identifier 'foo'.
+                    ~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
\ No newline at end of file
diff --git a/tests/baselines/reference/contextualSignatureInstantiation3.js b/tests/baselines/reference/contextualSignatureInstantiation3.js
new file mode 100644
index 00000000000..44737476482
--- /dev/null
+++ b/tests/baselines/reference/contextualSignatureInstantiation3.js
@@ -0,0 +1,42 @@
+//// [contextualSignatureInstantiation3.ts]
+function map<T, U>(items: T[], f: (x: T) => U): U[]{
+    return items.map(f);
+}
+
+function identity<T>(x: T) {
+    return x;
+}
+
+function singleton<T>(x: T) {
+    return [x];
+}
+
+var xs = [1, 2, 3];
+
+// Have compiler check that we get the correct types
+var v1: number[];
+var v1 = xs.map(identity);      // Error if not number[]
+var v1 = map(xs, identity);     // Error if not number[]
+
+var v2: number[][];         
+var v2 = xs.map(singleton);     // Error if not number[][]
+var v2 = map(xs, singleton);    // Error if not number[][]
+
+
+//// [contextualSignatureInstantiation3.js]
+function map(items, f) {
+    return items.map(f);
+}
+function identity(x) {
+    return x;
+}
+function singleton(x) {
+    return [x];
+}
+var xs = [1, 2, 3];
+var v1;
+var v1 = xs.map(identity);
+var v1 = map(xs, identity);
+var v2;
+var v2 = xs.map(singleton);
+var v2 = map(xs, singleton);
diff --git a/tests/baselines/reference/errorOnContextuallyTypedReturnType.errors.txt b/tests/baselines/reference/errorOnContextuallyTypedReturnType.errors.txt
index cb501a10e06..414fa7dc4c2 100644
--- a/tests/baselines/reference/errorOnContextuallyTypedReturnType.errors.txt
+++ b/tests/baselines/reference/errorOnContextuallyTypedReturnType.errors.txt
@@ -1,7 +1,9 @@
-==== tests/cases/compiler/errorOnContextuallyTypedReturnType.ts (1 errors) ====
+==== tests/cases/compiler/errorOnContextuallyTypedReturnType.ts (2 errors) ====
     var n1: () => boolean = function () { }; // expect an error here
         ~~
 !!! Type '() => void' is not assignable to type '() => boolean':
 !!!   Type 'void' is not assignable to type 'boolean'.
     var n2: () => boolean = function ():boolean { }; // expect an error here
+                                        ~~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     
\ No newline at end of file
diff --git a/tests/baselines/reference/functionImplementationErrors.errors.txt b/tests/baselines/reference/functionImplementationErrors.errors.txt
index d9d35c555ad..3da56bd6818 100644
--- a/tests/baselines/reference/functionImplementationErrors.errors.txt
+++ b/tests/baselines/reference/functionImplementationErrors.errors.txt
@@ -1,4 +1,4 @@
-==== tests/cases/conformance/functions/functionImplementationErrors.ts (6 errors) ====
+==== tests/cases/conformance/functions/functionImplementationErrors.ts (7 errors) ====
     // FunctionExpression with no return type annotation with multiple return statements with unrelated types
     var f1 = function () {
              ~~~~~~~~~~~~~
@@ -47,6 +47,8 @@
     
     // Function implemetnation with non -void return type annotation with no return
     function f5(): number {
+                   ~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     }
     
     var m;
diff --git a/tests/baselines/reference/functionWithThrowButNoReturn1.errors.txt b/tests/baselines/reference/functionWithThrowButNoReturn1.errors.txt
new file mode 100644
index 00000000000..b354a9f8852
--- /dev/null
+++ b/tests/baselines/reference/functionWithThrowButNoReturn1.errors.txt
@@ -0,0 +1,8 @@
+==== tests/cases/compiler/functionWithThrowButNoReturn1.ts (1 errors) ====
+    function fn(): number {
+                   ~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
+      throw new Error('NYI');
+      var t;
+    }
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/functionsMissingReturnStatementsAndExpressions.errors.txt b/tests/baselines/reference/functionsMissingReturnStatementsAndExpressions.errors.txt
new file mode 100644
index 00000000000..6ddbc91db57
--- /dev/null
+++ b/tests/baselines/reference/functionsMissingReturnStatementsAndExpressions.errors.txt
@@ -0,0 +1,129 @@
+==== tests/cases/compiler/functionsMissingReturnStatementsAndExpressions.ts (5 errors) ====
+    
+    function f1(): string {
+                   ~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
+        // errors because there are no return statements
+    }
+    
+    function f2(): string {
+        // Permissible; returns undefined.
+        return;
+    }
+    
+    function f3(): string {
+        return "Okay, because this is a return expression.";
+    }
+    
+    function f4(): void {
+        // Fine since we are typed void.
+    }
+    
+    function f5(): void {
+        // Fine since we are typed void.
+        return;
+    }
+    
+    function f6(): void {
+        // Fine since we are typed void and return undefined
+        return undefined;
+    }
+    
+    function f7(): void {
+        // Fine since we are typed void and return null
+        return null;
+    }
+    
+    function f8(): void {
+        // Fine since are typed any.
+        return;
+    }
+    
+    function f9(): void {
+        // Fine since we are typed any and return undefined
+        return undefined;
+    }
+    
+    function f10(): void {
+        // Fine since we are typed any and return null
+        return null;
+    }
+    
+    function f11(): string {
+        // Fine since we consist of a single throw statement.
+        throw undefined;
+    }
+    
+    function f12(): void {
+        // Fine since we consist of a single throw statement.
+        throw undefined;
+    }
+    
+    function f13(): any {
+        // Fine since we consist of a single throw statement.
+        throw undefined;
+    }
+    
+    function f14(): number {
+                    ~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
+        // Not fine, since we can *only* consist of a single throw statement
+        // if no return statements are present but we are annotated.
+        throw undefined;
+        throw null;
+    }
+    
+    function f15(): number {
+        // Fine, since we have a return statement somewhere.
+        throw undefined;
+        throw null;
+        return;
+    }
+    
+    
+    function f16() {
+        // Okay; not type annotated.
+    }
+    
+    function f17() {
+        // Okay; not type annotated.
+        return;
+    }
+    
+    function f18() {
+        return "Okay, not type annotated.";
+    }
+    
+    
+    class C {
+        public get m1() {
+                   ~~
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
+            // Errors; get accessors must return a value.
+        }
+    
+        public get m2() {
+            // Permissible; returns undefined.
+            return;
+        }
+    
+        public get m3() {
+            return "Okay, because this is a return expression.";
+        }
+    
+        public get m4() {
+            // Fine since this consists of a single throw statement.
+            throw null;
+        }
+    
+        public get m5() {
+                   ~~
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
+            // Not fine, since we can *only* consist of a single throw statement
+            // if no return statements are present but we are a get accessor.
+            throw null;
+            throw undefined.
+        }
+        ~
+!!! Identifier expected.
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.errors.txt b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.errors.txt
index 71545ae7503..1320a21f46b 100644
--- a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.errors.txt
+++ b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.errors.txt
@@ -1,8 +1,10 @@
-==== tests/cases/compiler/genericRecursiveImplicitConstructorErrors3.ts (7 errors) ====
+==== tests/cases/compiler/genericRecursiveImplicitConstructorErrors3.ts (8 errors) ====
     module TypeScript {
         export class MemberName <A,B,C>{
             static create<A,B,C>(arg1: any, arg2?: any, arg3?: any): MemberName {
                                                                      ~~~~~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
+                                                                     ~~~~~~~~~~
 !!! Generic type 'MemberName<A, B, C>' requires 3 type argument(s).
             }
         }
diff --git a/tests/baselines/reference/getterMissingReturnError.errors.txt b/tests/baselines/reference/getterMissingReturnError.errors.txt
index cf4f9b6b1a7..ae560c5de87 100644
--- a/tests/baselines/reference/getterMissingReturnError.errors.txt
+++ b/tests/baselines/reference/getterMissingReturnError.errors.txt
@@ -4,7 +4,7 @@
                    ~~
 !!! Accessors are only available when targeting ECMAScript 5 and higher.
                    ~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     
         }
     }
diff --git a/tests/baselines/reference/gettersAndSettersErrors.errors.txt b/tests/baselines/reference/gettersAndSettersErrors.errors.txt
index 1cfefea5202..dbd06a744f0 100644
--- a/tests/baselines/reference/gettersAndSettersErrors.errors.txt
+++ b/tests/baselines/reference/gettersAndSettersErrors.errors.txt
@@ -1,4 +1,4 @@
-==== tests/cases/compiler/gettersAndSettersErrors.ts (9 errors) ====
+==== tests/cases/compiler/gettersAndSettersErrors.ts (10 errors) ====
     class C {
         public get Foo() { return "foo";} // ok
                    ~~~
@@ -16,6 +16,8 @@
         public set Goo(v:string):string {} // error - setters must not specify a return type
                    ~~~
 !!! Accessors are only available when targeting ECMAScript 5 and higher.
+                                 ~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     }
     
     class E {
diff --git a/tests/baselines/reference/giant.errors.txt b/tests/baselines/reference/giant.errors.txt
index 35dddbb324e..f6b6dd5c796 100644
--- a/tests/baselines/reference/giant.errors.txt
+++ b/tests/baselines/reference/giant.errors.txt
@@ -26,7 +26,7 @@
                    ~~~
 !!! Duplicate identifier 'pgF'.
                    ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
         public psF(param:any) { }
         ~~~~~~
 !!! '{' expected.
@@ -40,7 +40,7 @@
                     ~~~
 !!! Duplicate identifier 'rgF'.
                     ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
         private rsF(param:any) { }
         ~~~~~~~
 !!! '{' expected.
@@ -62,7 +62,7 @@
                    ~~~
 !!! Duplicate identifier 'tgF'.
                    ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     }
     ~
 !!! '{' expected.
@@ -128,7 +128,7 @@
                        ~~~
 !!! Duplicate identifier 'pgF'.
                        ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
             public psF(param:any) { }
             ~~~~~~
 !!! '{' expected.
@@ -142,7 +142,7 @@
                         ~~~
 !!! Duplicate identifier 'rgF'.
                         ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
             private rsF(param:any) { }
             ~~~~~~~
 !!! '{' expected.
@@ -164,7 +164,7 @@
                        ~~~
 !!! Duplicate identifier 'tgF'.
                        ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
         }
         ~
 !!! '{' expected.
@@ -247,7 +247,7 @@
                        ~~~
 !!! Duplicate identifier 'pgF'.
                        ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
             public psF(param:any) { }
             ~~~~~~
 !!! '{' expected.
@@ -261,7 +261,7 @@
                         ~~~
 !!! Duplicate identifier 'rgF'.
                         ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
             private rsF(param:any) { }
             ~~~~~~~
 !!! '{' expected.
@@ -283,7 +283,7 @@
                        ~~~
 !!! Duplicate identifier 'tgF'.
                        ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
         }
         ~
 !!! '{' expected.
@@ -456,7 +456,7 @@
                    ~~~
 !!! Duplicate identifier 'pgF'.
                    ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
         public psF(param:any) { }
         ~~~~~~
 !!! '{' expected.
@@ -470,7 +470,7 @@
                     ~~~
 !!! Duplicate identifier 'rgF'.
                     ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
         private rsF(param:any) { }
         ~~~~~~~
 !!! '{' expected.
@@ -492,7 +492,7 @@
                    ~~~
 !!! Duplicate identifier 'tgF'.
                    ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     }
     ~
 !!! '{' expected.
@@ -558,7 +558,7 @@
                        ~~~
 !!! Duplicate identifier 'pgF'.
                        ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
             public psF(param:any) { }
             ~~~~~~
 !!! '{' expected.
@@ -572,7 +572,7 @@
                         ~~~
 !!! Duplicate identifier 'rgF'.
                         ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
             private rsF(param:any) { }
             ~~~~~~~
 !!! '{' expected.
@@ -594,7 +594,7 @@
                        ~~~
 !!! Duplicate identifier 'tgF'.
                        ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
         }
         ~
 !!! '{' expected.
@@ -677,7 +677,7 @@
                        ~~~
 !!! Duplicate identifier 'pgF'.
                        ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
             public psF(param:any) { }
             ~~~~~~
 !!! '{' expected.
@@ -691,7 +691,7 @@
                         ~~~
 !!! Duplicate identifier 'rgF'.
                         ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
             private rsF(param:any) { }
             ~~~~~~~
 !!! '{' expected.
@@ -713,7 +713,7 @@
                        ~~~
 !!! Duplicate identifier 'tgF'.
                        ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
         }
         ~
 !!! '{' expected.
diff --git a/tests/baselines/reference/indexSignatureTypeInference.errors.txt b/tests/baselines/reference/indexSignatureTypeInference.errors.txt
new file mode 100644
index 00000000000..097fef70921
--- /dev/null
+++ b/tests/baselines/reference/indexSignatureTypeInference.errors.txt
@@ -0,0 +1,23 @@
+==== tests/cases/compiler/indexSignatureTypeInference.ts (1 errors) ====
+    interface NumberMap<T> {
+        [index: number]: T;
+    }
+    
+    interface StringMap<T> {
+        [index: string]: T;
+    }
+    
+    declare function numberMapToArray<T>(object: NumberMap<T>): T[];
+    declare function stringMapToArray<T>(object: StringMap<T>): T[];
+    
+    var numberMap: NumberMap<Function>;
+    var stringMap: StringMap<Function>;
+    
+    var v1: Function[];
+    var v1 = numberMapToArray(numberMap);  // Ok
+    var v1 = numberMapToArray(stringMap);  // Ok
+    var v1 = stringMapToArray(numberMap);  // Error expected here
+             ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+!!! Supplied parameters do not match any signature of call target.
+    var v1 = stringMapToArray(stringMap);  // Ok
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/indexSignatureTypeInference.js b/tests/baselines/reference/indexSignatureTypeInference.js
new file mode 100644
index 00000000000..a4f79801258
--- /dev/null
+++ b/tests/baselines/reference/indexSignatureTypeInference.js
@@ -0,0 +1,30 @@
+//// [indexSignatureTypeInference.ts]
+interface NumberMap<T> {
+    [index: number]: T;
+}
+
+interface StringMap<T> {
+    [index: string]: T;
+}
+
+declare function numberMapToArray<T>(object: NumberMap<T>): T[];
+declare function stringMapToArray<T>(object: StringMap<T>): T[];
+
+var numberMap: NumberMap<Function>;
+var stringMap: StringMap<Function>;
+
+var v1: Function[];
+var v1 = numberMapToArray(numberMap);  // Ok
+var v1 = numberMapToArray(stringMap);  // Ok
+var v1 = stringMapToArray(numberMap);  // Error expected here
+var v1 = stringMapToArray(stringMap);  // Ok
+
+
+//// [indexSignatureTypeInference.js]
+var numberMap;
+var stringMap;
+var v1;
+var v1 = numberMapToArray(numberMap);
+var v1 = numberMapToArray(stringMap);
+var v1 = stringMapToArray(numberMap);
+var v1 = stringMapToArray(stringMap);
diff --git a/tests/baselines/reference/invalidReturnStatements.errors.txt b/tests/baselines/reference/invalidReturnStatements.errors.txt
index d870be638b9..ee371f5f000 100644
--- a/tests/baselines/reference/invalidReturnStatements.errors.txt
+++ b/tests/baselines/reference/invalidReturnStatements.errors.txt
@@ -1,9 +1,17 @@
-==== tests/cases/conformance/statements/returnStatements/invalidReturnStatements.ts (2 errors) ====
+==== tests/cases/conformance/statements/returnStatements/invalidReturnStatements.ts (6 errors) ====
     // all the following should be error
     function fn1(): number {  }
+                    ~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     function fn2(): string { }
+                    ~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     function fn3(): boolean { }
+                    ~~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     function fn4(): Date {  }
+                    ~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     function fn7(): any {  } // should be valid: any includes void
     
     interface I { id: number }
diff --git a/tests/baselines/reference/missingReturnStatement.errors.txt b/tests/baselines/reference/missingReturnStatement.errors.txt
new file mode 100644
index 00000000000..9a92adf4c03
--- /dev/null
+++ b/tests/baselines/reference/missingReturnStatement.errors.txt
@@ -0,0 +1,10 @@
+==== tests/cases/compiler/missingReturnStatement.ts (1 errors) ====
+    module Test {
+        export class Bug {
+            public foo():string {
+                         ~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
+            }
+        }    
+    }
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/missingReturnStatement1.errors.txt b/tests/baselines/reference/missingReturnStatement1.errors.txt
new file mode 100644
index 00000000000..d1d47368bb1
--- /dev/null
+++ b/tests/baselines/reference/missingReturnStatement1.errors.txt
@@ -0,0 +1,9 @@
+==== tests/cases/compiler/missingReturnStatement1.ts (1 errors) ====
+    class Foo {
+        foo(): number {
+               ~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
+            //return 4;
+        }
+    }
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/multiLineErrors.errors.txt b/tests/baselines/reference/multiLineErrors.errors.txt
index b01adc3bfb0..911c07731e3 100644
--- a/tests/baselines/reference/multiLineErrors.errors.txt
+++ b/tests/baselines/reference/multiLineErrors.errors.txt
@@ -1,10 +1,15 @@
-==== tests/cases/compiler/multiLineErrors.ts (1 errors) ====
+==== tests/cases/compiler/multiLineErrors.ts (2 errors) ====
     var t = 32;
     
     function noReturn(): {
+                         ~
         n: string;
+    ~~~~~~~~~~~~~~
         y: number;
+    ~~~~~~~~~~~~~~
     }
+    ~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     {
         var x = 4;
         var y = 10;
diff --git a/tests/baselines/reference/parserAccessors1.errors.txt b/tests/baselines/reference/parserAccessors1.errors.txt
index 4621637b211..76747e37104 100644
--- a/tests/baselines/reference/parserAccessors1.errors.txt
+++ b/tests/baselines/reference/parserAccessors1.errors.txt
@@ -2,5 +2,5 @@
     class C {
         get Foo() { }
             ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserAccessors3.errors.txt b/tests/baselines/reference/parserAccessors3.errors.txt
index 4d722dd1310..dd1f2075ae6 100644
--- a/tests/baselines/reference/parserAccessors3.errors.txt
+++ b/tests/baselines/reference/parserAccessors3.errors.txt
@@ -1,4 +1,4 @@
 ==== tests/cases/conformance/parser/ecmascript5/Accessors/parserAccessors3.ts (1 errors) ====
     var v = { get Foo() { } };
                   ~~~
-!!! Getters must return a value.
\ No newline at end of file
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
\ No newline at end of file
diff --git a/tests/baselines/reference/parserAccessors7.errors.txt b/tests/baselines/reference/parserAccessors7.errors.txt
index 13597d19f71..cac6f016814 100644
--- a/tests/baselines/reference/parserAccessors7.errors.txt
+++ b/tests/baselines/reference/parserAccessors7.errors.txt
@@ -3,4 +3,4 @@
                   ~~~
 !!! A 'get' accessor cannot have parameters.
                   ~~~
-!!! Getters must return a value.
\ No newline at end of file
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
\ No newline at end of file
diff --git a/tests/baselines/reference/parserES3Accessors1.errors.txt b/tests/baselines/reference/parserES3Accessors1.errors.txt
index 3ab21b3001e..53bfc5e868e 100644
--- a/tests/baselines/reference/parserES3Accessors1.errors.txt
+++ b/tests/baselines/reference/parserES3Accessors1.errors.txt
@@ -4,5 +4,5 @@
             ~~~
 !!! Accessors are only available when targeting ECMAScript 5 and higher.
             ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserES3Accessors3.errors.txt b/tests/baselines/reference/parserES3Accessors3.errors.txt
index 3678eb94dc1..74a79ccf6d8 100644
--- a/tests/baselines/reference/parserES3Accessors3.errors.txt
+++ b/tests/baselines/reference/parserES3Accessors3.errors.txt
@@ -3,4 +3,4 @@
                   ~~~
 !!! Accessors are only available when targeting ECMAScript 5 and higher.
                   ~~~
-!!! Getters must return a value.
\ No newline at end of file
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
\ No newline at end of file
diff --git a/tests/baselines/reference/parserErrorRecovery_Block3.errors.txt b/tests/baselines/reference/parserErrorRecovery_Block3.errors.txt
index 15bc9ad3385..354cfff1fdd 100644
--- a/tests/baselines/reference/parserErrorRecovery_Block3.errors.txt
+++ b/tests/baselines/reference/parserErrorRecovery_Block3.errors.txt
@@ -1,9 +1,13 @@
-==== tests/cases/conformance/parser/ecmascript5/ErrorRecovery/Blocks/parserErrorRecovery_Block3.ts (1 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/ErrorRecovery/Blocks/parserErrorRecovery_Block3.ts (3 errors) ====
     class C  {
         private a(): boolean {
+                     ~~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     
         private b(): boolean {
         ~~~~~~~
 !!! Statement expected.
+                     ~~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
         }
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserGenericsInTypeContexts1.errors.txt b/tests/baselines/reference/parserGenericsInTypeContexts1.errors.txt
index 2239f1ff993..574c03823df 100644
--- a/tests/baselines/reference/parserGenericsInTypeContexts1.errors.txt
+++ b/tests/baselines/reference/parserGenericsInTypeContexts1.errors.txt
@@ -1,4 +1,4 @@
-==== tests/cases/conformance/parser/ecmascript5/Generics/parserGenericsInTypeContexts1.ts (9 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/Generics/parserGenericsInTypeContexts1.ts (10 errors) ====
     class C extends A<T> implements B<T> {
                     ~~~~
 !!! Cannot find name 'A'.
@@ -30,6 +30,8 @@
     
     function f2(): F<T> {
                    ~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
+                   ~~~~
 !!! Cannot find name 'F'.
     }
     
diff --git a/tests/baselines/reference/parserGenericsInTypeContexts2.errors.txt b/tests/baselines/reference/parserGenericsInTypeContexts2.errors.txt
index b99d6826169..f3b47f04368 100644
--- a/tests/baselines/reference/parserGenericsInTypeContexts2.errors.txt
+++ b/tests/baselines/reference/parserGenericsInTypeContexts2.errors.txt
@@ -1,4 +1,4 @@
-==== tests/cases/conformance/parser/ecmascript5/Generics/parserGenericsInTypeContexts2.ts (9 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/Generics/parserGenericsInTypeContexts2.ts (10 errors) ====
     class C extends A<X<T>, Y<Z<T>>> implements B<X<T>, Y<Z<T>>> {
                     ~~~~~~~~~~~~~~~~
 !!! Cannot find name 'A'.
@@ -30,6 +30,8 @@
     
     function f2(): F<X<T>, Y<Z<T>>> {
                    ~~~~~~~~~~~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
+                   ~~~~~~~~~~~~~~~~
 !!! Cannot find name 'F'.
     }
     
diff --git a/tests/baselines/reference/parserGetAccessorWithTypeParameters1.errors.txt b/tests/baselines/reference/parserGetAccessorWithTypeParameters1.errors.txt
index 33705621fb8..0f290dbd8ab 100644
--- a/tests/baselines/reference/parserGetAccessorWithTypeParameters1.errors.txt
+++ b/tests/baselines/reference/parserGetAccessorWithTypeParameters1.errors.txt
@@ -4,5 +4,5 @@
           ~~~
 !!! An accessor cannot have type parameters.
           ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserMemberAccessor1.errors.txt b/tests/baselines/reference/parserMemberAccessor1.errors.txt
index cc64233237b..c768b0ce2fe 100644
--- a/tests/baselines/reference/parserMemberAccessor1.errors.txt
+++ b/tests/baselines/reference/parserMemberAccessor1.errors.txt
@@ -2,6 +2,6 @@
     class C {
       get foo() { }
           ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
       set foo(a) { }
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserMemberAccessorDeclaration1.errors.txt b/tests/baselines/reference/parserMemberAccessorDeclaration1.errors.txt
index a052f03808e..403a30a67ae 100644
--- a/tests/baselines/reference/parserMemberAccessorDeclaration1.errors.txt
+++ b/tests/baselines/reference/parserMemberAccessorDeclaration1.errors.txt
@@ -2,5 +2,5 @@
     class C {
       get a() { }
           ~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserMemberAccessorDeclaration10.errors.txt b/tests/baselines/reference/parserMemberAccessorDeclaration10.errors.txt
index 8ea973bbb29..a1b29085f5d 100644
--- a/tests/baselines/reference/parserMemberAccessorDeclaration10.errors.txt
+++ b/tests/baselines/reference/parserMemberAccessorDeclaration10.errors.txt
@@ -4,5 +4,5 @@
         ~~~~~~
 !!! 'export' modifier cannot appear on a class element.
                    ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserMemberAccessorDeclaration12.errors.txt b/tests/baselines/reference/parserMemberAccessorDeclaration12.errors.txt
index d3ca95a6bc2..7cbf2606274 100644
--- a/tests/baselines/reference/parserMemberAccessorDeclaration12.errors.txt
+++ b/tests/baselines/reference/parserMemberAccessorDeclaration12.errors.txt
@@ -4,5 +4,5 @@
            ~~~
 !!! A 'get' accessor cannot have parameters.
            ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserMemberAccessorDeclaration2.errors.txt b/tests/baselines/reference/parserMemberAccessorDeclaration2.errors.txt
index 3cdd230ad65..1a32d342f1b 100644
--- a/tests/baselines/reference/parserMemberAccessorDeclaration2.errors.txt
+++ b/tests/baselines/reference/parserMemberAccessorDeclaration2.errors.txt
@@ -2,5 +2,5 @@
     class C {
       get "b"() { }
           ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserMemberAccessorDeclaration3.errors.txt b/tests/baselines/reference/parserMemberAccessorDeclaration3.errors.txt
index 53a0dd84fac..dbf94b6420f 100644
--- a/tests/baselines/reference/parserMemberAccessorDeclaration3.errors.txt
+++ b/tests/baselines/reference/parserMemberAccessorDeclaration3.errors.txt
@@ -2,5 +2,5 @@
     class C {
       get 0() { }
           ~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserMemberAccessorDeclaration7.errors.txt b/tests/baselines/reference/parserMemberAccessorDeclaration7.errors.txt
index 614c1251aa4..20ebd2f3583 100644
--- a/tests/baselines/reference/parserMemberAccessorDeclaration7.errors.txt
+++ b/tests/baselines/reference/parserMemberAccessorDeclaration7.errors.txt
@@ -4,5 +4,5 @@
                ~~~~~~
 !!! Accessibility modifier already seen.
                           ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserMemberAccessorDeclaration8.errors.txt b/tests/baselines/reference/parserMemberAccessorDeclaration8.errors.txt
index f28ee32f00e..f6d151bfb7f 100644
--- a/tests/baselines/reference/parserMemberAccessorDeclaration8.errors.txt
+++ b/tests/baselines/reference/parserMemberAccessorDeclaration8.errors.txt
@@ -4,5 +4,5 @@
                ~~~~~~
 !!! 'static' modifier already seen.
                           ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserMemberAccessorDeclaration9.errors.txt b/tests/baselines/reference/parserMemberAccessorDeclaration9.errors.txt
index d2a52098aa7..e4c88dfd57d 100644
--- a/tests/baselines/reference/parserMemberAccessorDeclaration9.errors.txt
+++ b/tests/baselines/reference/parserMemberAccessorDeclaration9.errors.txt
@@ -4,5 +4,5 @@
                ~~~~~~
 !!! 'public' modifier must precede 'static' modifier.
                           ~~~
-!!! Getters must return a value.
+!!! A 'get' accessor must return a value or consist of a single 'throw' statement.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserParameterList5.errors.txt b/tests/baselines/reference/parserParameterList5.errors.txt
index c8a9aa31b78..ccc5d8c0dbf 100644
--- a/tests/baselines/reference/parserParameterList5.errors.txt
+++ b/tests/baselines/reference/parserParameterList5.errors.txt
@@ -1,5 +1,7 @@
-==== tests/cases/conformance/parser/ecmascript5/ParameterLists/parserParameterList5.ts (2 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/ParameterLists/parserParameterList5.ts (3 errors) ====
     function A(): (public B) => C {
+                  ~~~~~~~~~~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
                    ~~~~~~~~
 !!! A parameter property is only allowed in a constructor implementation.
                                 ~
diff --git a/tests/baselines/reference/parserSetAccessorWithTypeAnnotation1.errors.txt b/tests/baselines/reference/parserSetAccessorWithTypeAnnotation1.errors.txt
index 135f06cf304..f4898163e0f 100644
--- a/tests/baselines/reference/parserSetAccessorWithTypeAnnotation1.errors.txt
+++ b/tests/baselines/reference/parserSetAccessorWithTypeAnnotation1.errors.txt
@@ -1,7 +1,9 @@
-==== tests/cases/conformance/parser/ecmascript5/Accessors/parserSetAccessorWithTypeAnnotation1.ts (1 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/Accessors/parserSetAccessorWithTypeAnnotation1.ts (2 errors) ====
     class C {
        set foo(v): number {
            ~~~
 !!! A 'set' accessor cannot have a return type annotation.
+                   ~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
        }
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/recursiveFunctionTypes.errors.txt b/tests/baselines/reference/recursiveFunctionTypes.errors.txt
index e14d3a38a5c..833fcf386c0 100644
--- a/tests/baselines/reference/recursiveFunctionTypes.errors.txt
+++ b/tests/baselines/reference/recursiveFunctionTypes.errors.txt
@@ -1,4 +1,4 @@
-==== tests/cases/compiler/recursiveFunctionTypes.ts (10 errors) ====
+==== tests/cases/compiler/recursiveFunctionTypes.ts (12 errors) ====
     function fn(): typeof fn { return 1; }
                                       ~
 !!! Type 'number' is not assignable to type '() => typeof fn'.
@@ -17,7 +17,11 @@
     function f1(d: typeof f1) { }
     
     function f2(): typeof g2 { } 
+                   ~~~~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     function g2(): typeof f2 { } 
+                   ~~~~~~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     
     interface I<T> { }
     function f3(): I<typeof f3> { return f3; }
diff --git a/tests/baselines/reference/returnTypeParameter.errors.txt b/tests/baselines/reference/returnTypeParameter.errors.txt
index 1490825c77a..f8927fef427 100644
--- a/tests/baselines/reference/returnTypeParameter.errors.txt
+++ b/tests/baselines/reference/returnTypeParameter.errors.txt
@@ -1,5 +1,7 @@
-==== tests/cases/compiler/returnTypeParameter.ts (1 errors) ====
+==== tests/cases/compiler/returnTypeParameter.ts (2 errors) ====
     function f<T>(a: T): T { } // error, no return statement
+                         ~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
     function f2<T>(a: T): T { return T; } // bug was that this satisfied the return statement requirement
                                      ~
 !!! Cannot find name 'T'.
\ No newline at end of file
diff --git a/tests/baselines/reference/typeParameterUsedAsTypeParameterConstraint4.errors.txt b/tests/baselines/reference/typeParameterUsedAsTypeParameterConstraint4.errors.txt
index 9903408f70b..da073522ae8 100644
--- a/tests/baselines/reference/typeParameterUsedAsTypeParameterConstraint4.errors.txt
+++ b/tests/baselines/reference/typeParameterUsedAsTypeParameterConstraint4.errors.txt
@@ -1,4 +1,4 @@
-==== tests/cases/conformance/types/objectTypeLiteral/callSignatures/typeParameterUsedAsTypeParameterConstraint4.ts (25 errors) ====
+==== tests/cases/conformance/types/objectTypeLiteral/callSignatures/typeParameterUsedAsTypeParameterConstraint4.ts (29 errors) ====
     // Type parameters are in scope in their own and other type parameter lists
     // Some negative cases
     
@@ -35,9 +35,13 @@
                     ~~~~~~~~~~~
 !!! Constraint of a type parameter cannot reference any type parameter from the same type parameter list.
                                               ~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
+                                              ~
 !!! Cannot find name 'V'.
         function bar<V extends T, W extends U>(): X { // error
                                                   ~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
+                                                  ~
 !!! Cannot find name 'X'.
             function baz<X extends W, Y extends V>(a: X, b: Y): T {
                 x = y;
@@ -54,9 +58,13 @@
                   ~~~~~~~~~~~
 !!! Constraint of a type parameter cannot reference any type parameter from the same type parameter list.
                                                ~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
+                                               ~
 !!! Cannot find name 'W'.
         function bar<V extends T, W extends U>(): Y { // error
                                                   ~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
+                                                  ~
 !!! Cannot find name 'Y'.
             function baz<X extends W, Y extends V>(a: X, b: Y): T {
                 x = y;
diff --git a/tests/baselines/reference/unknownSymbols1.errors.txt b/tests/baselines/reference/unknownSymbols1.errors.txt
index 220d7ba0ddb..beb39743441 100644
--- a/tests/baselines/reference/unknownSymbols1.errors.txt
+++ b/tests/baselines/reference/unknownSymbols1.errors.txt
@@ -1,4 +1,4 @@
-==== tests/cases/compiler/unknownSymbols1.ts (13 errors) ====
+==== tests/cases/compiler/unknownSymbols1.ts (14 errors) ====
     var x = asdf;
             ~~~~
 !!! Cannot find name 'asdf'.
@@ -10,6 +10,8 @@
                     ~~~~
 !!! Cannot find name 'asdf'.
                                       ~~~~
+!!! A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
+                                      ~~~~
 !!! Cannot find name 'asdf'.
     function foo2() {
         return asdf;
diff --git a/tests/cases/compiler/contextualSignatureInstantiation3.ts b/tests/cases/compiler/contextualSignatureInstantiation3.ts
new file mode 100644
index 00000000000..a71f08d209d
--- /dev/null
+++ b/tests/cases/compiler/contextualSignatureInstantiation3.ts
@@ -0,0 +1,22 @@
+function map<T, U>(items: T[], f: (x: T) => U): U[]{
+    return items.map(f);
+}
+
+function identity<T>(x: T) {
+    return x;
+}
+
+function singleton<T>(x: T) {
+    return [x];
+}
+
+var xs = [1, 2, 3];
+
+// Have compiler check that we get the correct types
+var v1: number[];
+var v1 = xs.map(identity);      // Error if not number[]
+var v1 = map(xs, identity);     // Error if not number[]
+
+var v2: number[][];         
+var v2 = xs.map(singleton);     // Error if not number[][]
+var v2 = map(xs, singleton);    // Error if not number[][]
diff --git a/tests/cases/compiler/functionsMissingReturnStatementsAndExpressions.ts b/tests/cases/compiler/functionsMissingReturnStatementsAndExpressions.ts
new file mode 100644
index 00000000000..81259fd7c0c
--- /dev/null
+++ b/tests/cases/compiler/functionsMissingReturnStatementsAndExpressions.ts
@@ -0,0 +1,119 @@
+// @target: es5
+
+function f1(): string {
+    // errors because there are no return statements
+}
+
+function f2(): string {
+    // Permissible; returns undefined.
+    return;
+}
+
+function f3(): string {
+    return "Okay, because this is a return expression.";
+}
+
+function f4(): void {
+    // Fine since we are typed void.
+}
+
+function f5(): void {
+    // Fine since we are typed void.
+    return;
+}
+
+function f6(): void {
+    // Fine since we are typed void and return undefined
+    return undefined;
+}
+
+function f7(): void {
+    // Fine since we are typed void and return null
+    return null;
+}
+
+function f8(): void {
+    // Fine since are typed any.
+    return;
+}
+
+function f9(): void {
+    // Fine since we are typed any and return undefined
+    return undefined;
+}
+
+function f10(): void {
+    // Fine since we are typed any and return null
+    return null;
+}
+
+function f11(): string {
+    // Fine since we consist of a single throw statement.
+    throw undefined;
+}
+
+function f12(): void {
+    // Fine since we consist of a single throw statement.
+    throw undefined;
+}
+
+function f13(): any {
+    // Fine since we consist of a single throw statement.
+    throw undefined;
+}
+
+function f14(): number {
+    // Not fine, since we can *only* consist of a single throw statement
+    // if no return statements are present but we are annotated.
+    throw undefined;
+    throw null;
+}
+
+function f15(): number {
+    // Fine, since we have a return statement somewhere.
+    throw undefined;
+    throw null;
+    return;
+}
+
+
+function f16() {
+    // Okay; not type annotated.
+}
+
+function f17() {
+    // Okay; not type annotated.
+    return;
+}
+
+function f18() {
+    return "Okay, not type annotated.";
+}
+
+
+class C {
+    public get m1() {
+        // Errors; get accessors must return a value.
+    }
+
+    public get m2() {
+        // Permissible; returns undefined.
+        return;
+    }
+
+    public get m3() {
+        return "Okay, because this is a return expression.";
+    }
+
+    public get m4() {
+        // Fine since this consists of a single throw statement.
+        throw null;
+    }
+
+    public get m5() {
+        // Not fine, since we can *only* consist of a single throw statement
+        // if no return statements are present but we are a get accessor.
+        throw null;
+        throw undefined.
+    }
+}
\ No newline at end of file
diff --git a/tests/cases/compiler/indexSignatureTypeInference.ts b/tests/cases/compiler/indexSignatureTypeInference.ts
new file mode 100644
index 00000000000..66fcb53d76c
--- /dev/null
+++ b/tests/cases/compiler/indexSignatureTypeInference.ts
@@ -0,0 +1,19 @@
+interface NumberMap<T> {
+    [index: number]: T;
+}
+
+interface StringMap<T> {
+    [index: string]: T;
+}
+
+declare function numberMapToArray<T>(object: NumberMap<T>): T[];
+declare function stringMapToArray<T>(object: StringMap<T>): T[];
+
+var numberMap: NumberMap<Function>;
+var stringMap: StringMap<Function>;
+
+var v1: Function[];
+var v1 = numberMapToArray(numberMap);  // Ok
+var v1 = numberMapToArray(stringMap);  // Ok
+var v1 = stringMapToArray(numberMap);  // Error expected here
+var v1 = stringMapToArray(stringMap);  // Ok