Type Alias Err<E>

Check if Result is Ok.

Check if Result is Err.

Map Result's success value to a new value by providing a transformation function.

Returns a new Result<UpdatedType, ErrorType>:

const x = Ok<number>(42); // Result<number, never>
const y = x.map<string>((x: number) => x.toString()) // Result<string, never>
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Does nothing if the Result is not Ok:

const x = Err<number>(42); // Result<never, number>
const y = x.map<string>((x: number) => x.toString()) // Result<never, number>
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Map Result's error value to a new value by providing a transformation function.

Returns a new Result<SuccessType, NewErrorType>:

const x = Err<number>(42); // Result<never, number>
const y = x.mapErr<string>((x: number) => x.toString()) // Result<never, string>
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Does nothing if the Result is not Err:

const x = Ok<number>(42); // Result<number, never>
const y = x.mapErr<string>((x: number) => x.toString()) // Result<number, never>
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