Typescript one of array

function stringLiterals<T extends string>(...args: T[]): T[] { return args; }
type ElementType<T extends ReadonlyArray<unknown>> = T extends ReadonlyArray<infer ElementType> ? ElementType : never;

const values = stringLiterals('A', 'B');
type Foo = ElementType<typeof values>;

const v1: Foo = 'A' // This should work
const v2: Foo = 'D' // This should give me an error since 'D' doesn't exist in values

Source: github.com

Typescript one of the array items

const animals = ['cat', 'dog', 'mouse'] as const
type Animal = typeof animals[number]

// type Animal = 'cat' | 'dog' | 'mouse'

Source: steveholgado.com

Similar codes

2 votes110 views1 answer
Visual Studio Code Typescript region folding
TypeScript
0 vote146 views3 answers
Highcharts cdn links
TypeScript
-1 vote147 views1 answer
What was in Rome that helped Renaissance artists achieve their goal of Humanism?
TypeScript
11 votes158 views5 answers
Shortcode_atts wordpress
TypeScript
2 votes166 views1 answer
Adding headers to httpclient angular
TypeScript
1 vote152 views1 answer
Whats ruby used for
TypeScript
1 vote141 views1 answer
Sass migrate division vue
TypeScript
1 vote133 views1 answer
Npm type-check nested arrays
TypeScript
0 vote150 views1 answer
Typeorm @unique
TypeScript
0 vote142 views1 answer
No corners in broder css
TypeScript