Function: mapOr()
Call Signature
mapOr<
T,U,E>(orU,mapFn,result):U
Map over a Result instance as in map and get out the value if result is an Ok, or return a default value if result is an Err.
Examples
import { ok, err, mapOr } from 'true-myth/result';
const length = (s: string) => s.length;
const anOkString = ok('a string');
const theStringLength = mapOr(0, length, anOkString);
console.log(theStringLength); // 8
const anErr = err('uh oh');
const anErrMapped = mapOr(0, length, anErr);
console.log(anErrMapped); // 0Type Parameters
T
T
U
U
E
E
Parameters
orU
U
The default value to use if result is an Err.
mapFn
(t) => U
The function to apply the value to if result is an Ok.
result
Result<T, E>
The Result instance to map over.
Returns
U
Call Signature
mapOr<
T,U,E>(orU,mapFn): (result) =>U
Map over a Result instance as in map and get out the value if result is an Ok, or return a default value if result is an Err.
Examples
import { ok, err, mapOr } from 'true-myth/result';
const length = (s: string) => s.length;
const anOkString = ok('a string');
const theStringLength = mapOr(0, length, anOkString);
console.log(theStringLength); // 8
const anErr = err('uh oh');
const anErrMapped = mapOr(0, length, anErr);
console.log(anErrMapped); // 0Type Parameters
T
T
U
U
E
E
Parameters
orU
U
The default value to use if result is an Err.
mapFn
(t) => U
The function to apply the value to if result is an Ok.
Returns
(
result):U
Parameters
result
Result<T, E>
Returns
U
Call Signature
mapOr<
T,U,E>(orU): (mapFn) => (result) =>U
Map over a Result instance as in map and get out the value if result is an Ok, or return a default value if result is an Err.
Examples
import { ok, err, mapOr } from 'true-myth/result';
const length = (s: string) => s.length;
const anOkString = ok('a string');
const theStringLength = mapOr(0, length, anOkString);
console.log(theStringLength); // 8
const anErr = err('uh oh');
const anErrMapped = mapOr(0, length, anErr);
console.log(anErrMapped); // 0Type Parameters
T
T
U
U
E
E
Parameters
orU
U
The default value to use if result is an Err.
Returns
(
mapFn): (result) =>U
Parameters
mapFn
(t) => U
Returns
(
result):U
Parameters
result
Result<T, E>
Returns
U