mapErr

mapErr<E, F>(f): <A>(data) => These<F, A>

Defined in: Core/These.ts:114

Transforms the error/warning value, leaving the success value unchanged.

Type Parameters

E

E

F

F

Parameters

f

(e) => F

Returns

<A>(data): These<F, A>

Type Parameters

A

A

Parameters

data

These<E, A>

Returns

These<F, A>

Example

pipe(These.err("err"), These.mapErr(e => e.toUpperCase()));         // Err("ERR")
pipe(These.both("warn", 5), These.mapErr(e => e.toUpperCase()));    // Both("WARN", 5)