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Addressing CR feedback

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This commit is contained in:
Anders Hejlsberg
2015-01-26 13:09:23 -08:00
parent 0410394de0
commit 75404a7e00
1 changed files with 12 additions and 8 deletions
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20
src/compiler/checker.ts
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@@ -4469,14 +4469,16 @@ module ts {
Debug.fail("should not get here");
}
// For a union type, remove all constituent types for which the given flags have the given state
function removeTypesFromUnionType(type: Type, maskFlags: TypeFlags, maskState: boolean): Type {
// For a union type, remove all constituent types for that are of the given type kind (when isOfTypeKind is true)
// or not of the given type kind (when isOfTypeKind is false)
function removeTypesFromUnionType(type: Type, typeKind: TypeFlags, isOfTypeKind: boolean): Type {
if (type.flags & TypeFlags.Union) {
var types = (<UnionType>type).types;
if (forEach(types, t => !(t.flags & maskFlags) !== maskState)) {
var reducedType = getUnionType(filter(types, t => !(t.flags & maskFlags) === maskState));
if (reducedType !== emptyObjectType) {
return reducedType;
if (forEach(types, t => !!(t.flags & typeKind) === isOfTypeKind)) {
// Above we checked if we have anything to remove, now use the opposite test to do the removal
var narrowedType = getUnionType(filter(types, t => !(t.flags & typeKind) === isOfTypeKind));
if (narrowedType !== emptyObjectType) {
return narrowedType;
}
}
}
@@ -4687,7 +4689,8 @@ module ts {
if (isTypeSubtypeOf(typeInfo.type, type)) {
return typeInfo.type;
}
// Otherwise, remove all types that aren't of the primitive type kind
// Otherwise, remove all types that aren't of the primitive type kind. This can happen when the type is
// union of enum types and other types.
return removeTypesFromUnionType(type, typeInfo.flags, false);
}
else {
@@ -4757,7 +4760,8 @@ module ts {
return type;
}
// Narrow the given type based on the given expression having the assumed boolean value
// Narrow the given type based on the given expression having the assumed boolean value. The returned type
// will be a subtype or the same type as the argument.
function narrowType(type: Type, expr: Expression, assumeTrue: boolean): Type {
switch (expr.kind) {
case SyntaxKind.ParenthesizedExpression: