HintedString

See source on Github 

Prevent TypeScript from collapsing a union of string literals into string. Useful when union should be part of IntelliSense suggestions, but any string value is also accepted.

Example

type Union = 'foo' | 'bar'
 
type Unhinted = Union | string // string
type Hinted = HintedString<Union> // 'foo' | 'bar' | string