microsoft/TypeScript
1
0
Fork 0
mirror of https://github.com/microsoft/TypeScript.git synced 2026-02-06 20:14:01 -06:00
Code Issues Packages Projects Releases 212 Wiki Activity

Update comment

Browse Source
This commit is contained in:
Anders Hejlsberg 2016-08-08 09:44:24 -07:00
parent 67b3fe58fa
commit a0c5608770
1 changed files with 4 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
src/compiler/checker.ts
View File

@ -8538,9 +8538,10 @@ namespace ts {
}
}
// If the candidate type is a subtype of the target type, narrow to the candidate type.
// Otherwise, narrow to whichever of the target type or the candidate type that is assignable
// to the other. Otherwise, the types are completely unrelated, so narrow to an intersection
// of the two types.
// Otherwise, if the target type is assignable to the candidate type, keep the target type.
// Otherwise, if the candidate type is assignable to the target type, narrow to the candidate
// type. Otherwise, the types are completely unrelated, so narrow to an intersection of the
// two types.
const targetType = type.flags & TypeFlags.TypeParameter ? getApparentType(type) : type;
return isTypeSubtypeOf(candidate, targetType) ? candidate :
isTypeAssignableTo(type, candidate) ? type :