Interface IResultBuild<IsOk, OkType, ErrType>

Result builder interface

Since

v1.0.0

interface IResultBuild<IsOk = true, OkType = unknown, ErrType = unknown> {
    isErr: IsOk extends false ? true : false;
    isOk: IsOk;
    and<CompareType>(
        value: IResult<CompareType>,
    ): IsOk extends true
        ? IResult<CompareType, unknown>
        : IResultBuild<IsOk, OkType, ErrType>;
    andThen<OutResult extends IResult<unknown, unknown>>(
        callbackFunc: (val: IsOk extends true ? OkType : never) => OutResult,
    ): IsOk extends true ? OutResult : IResultBuild<IsOk, OkType, ErrType>;
    andThenPromise<OutResult extends IResult<unknown, unknown>>(
        callbackFunc: (
            val: IsOk extends true ? OkType : never,
        ) => Promise<OutResult>,
    ): IsOk extends true
        ? Promise<OutResult>
        : IResultBuild<IsOk, OkType, ErrType>;
    clone(): IResultBuild<IsOk, OkType, ErrType>;
    eq(other: IResult): boolean;
    err(): IsOk extends false ? ErrType : undefined;
    inspect(fn: (value: OkType) => void): this;
    inspectErr(fn: (value: ErrType) => void): this;
    isErrAnd(
        callbackFunc: (value: ErrType) => boolean,
    ): IsOk extends false ? boolean : false;
    isOkAnd(
        callbackFunc: (value: OkType) => boolean,
    ): IsOk extends true ? boolean : false;
    iter(): IterableIterator<
        IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : INone,
        IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : INone,
    >;
    map<NewOkType>(
        fn: (value: OkType) => NewOkType,
    ): IsOk extends true ? IOk<NewOkType> : IResultBuild<IsOk, OkType, ErrType>;
    mapErr<NewErrType>(
        fn: (value: ErrType) => NewErrType,
    ): IsOk extends true
        ? IResultBuild<IsOk, OkType, ErrType>
        : IErr<NewErrType>;
    ok(): IsOk extends true ? OkType : undefined;
    or<CompareType>(
        value: IResult<CompareType>,
    ): IsOk extends true
        ? IResultBuild<IsOk, OkType, ErrType>
        : IResult<CompareType, unknown>;
    orElse<OutResult extends IResult<unknown, unknown>>(
        callbackFunc: (value: IsOk extends true ? never : ErrType) => OutResult,
    ): IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : OutResult;
    orElsePromise<OutResult extends IResult<unknown, unknown>>(
        callbackFunc: (
            value: IsOk extends true ? never : ErrType,
        ) => Promise<OutResult>,
    ): IsOk extends true
        ? IResultBuild<IsOk, OkType, ErrType>
        : Promise<OutResult>;
    toJSON(): IsOk extends true ? IJsonOk<OkType> : IJsonErr<ErrType>;
    toOption(): IsOk extends true ? ISome<OkType> : INone<never>;
    toString(): IsOk extends true ? `Ok(${string})` : `Err(${string})`;
    unwrap(): IsOk extends true ? OkType : never;
    unwrapOr<DefaultType>(
        defaultValue: DefaultType,
    ): IsOk extends true ? OkType : DefaultType;
    unwrapOrElse<DefaultType>(
        callbackFunc: () => DefaultType,
    ): IsOk extends true ? OkType : DefaultType;
    unwrapOrValueOf<ValueType>(
        BaseConstructor: ConstructorWithValueOf<ValueType>,
    ): IsOk extends true ? OkType : ValueType;
}

Type Parameters

IsOk = true
OkType = unknown
ErrType = unknown

Implemented by

Index

Properties

isErr isOk

Methods

and andThen andThenPromise clone eq err inspect inspectErr isErrAnd isOkAnd iter map mapErr ok or orElse orElsePromise toJSON toOption toString unwrap unwrapOr unwrapOrElse unwrapOrValueOf

Properties

isErr

isErr: IsOk extends false ? true : false

Check that result is an error

Returns

true if result is an error

Example

Ok<number>(2).isErr // false
Err<Error>(new Error('broken')).isErr // true

isOk

isOk: IsOk

Check that result is not an error

Returns

true if result is not an error

Example

Ok<number>(2).isOk // true
Err<Error>(new Error('broken')).isOk // false

Methods

and

and<CompareType>(
    value: IResult<CompareType>,
): IsOk extends true
    ? IResult<CompareType, unknown>
    : IResultBuild<IsOk, OkType, ErrType>
Method to combine two results, if the first result is true return the second result, otherwise return the first result
Type Parameters
- CompareType
Parameters
- value: IResult<CompareType>
  compare value
Returns IsOk extends true
? IResult<CompareType, unknown>
: IResultBuild<IsOk, OkType, ErrType>
- Result based on the self value and the value parameter
Example
```
Err<Error>(new Error('broken')).and(Ok<number>(3)) // Err<Error>(new Error('broken'))
Ok<number>(2).and(Err<number>(new Error('broken'))) // Err<Error>(new Error('broken'))
Ok<number>(2).and(Ok<number>(3)) // Ok<number>(3)
```
- Defined in src/interfaces/IResultImplementation.mts:121

andThen

andThen<OutResult extends IResult<unknown, unknown>>(
callbackFunc: (val: IsOk extends true ? OkType : never) => OutResult,
): IsOk extends true ? OutResult : IResultBuild<IsOk, OkType, ErrType>
Method to combine two results, if the first result is true use the value to build a new result, otherwise return the error
Type Parameters
- OutResult extends IResult<unknown, unknown>
Parameters
- callbackFunc: (val: IsOk extends true ? OkType : never) => OutResult
  callback to build a new result
Returns IsOk extends true ? OutResult : IResultBuild<IsOk, OkType, ErrType>
- Result based on the self value and the value parameter
Example
```
Ok<number>(2).andThen<IResult<number>>((val) => Ok(val + 1)) // Ok<number>(3)
Err<'broken'>('broken').andThen<IResult<number>>((val) => Ok(val + 1)) // Err<'broken'>('broken')
```
- Defined in src/interfaces/IResultImplementation.mts:130

andThenPromise

andThenPromise<OutResult extends IResult<unknown, unknown>>(
    callbackFunc: (
        val: IsOk extends true ? OkType : never,
    ) => Promise<OutResult>,
): IsOk extends true
    ? Promise<OutResult>
    : IResultBuild<IsOk, OkType, ErrType>
Method to combine two results, if the first result is true use the value to build a new result from Promise, otherwise return the error
Type Parameters
- OutResult extends IResult<unknown, unknown>
Parameters
- callbackFunc: (val: IsOk extends true ? OkType : never) => Promise<OutResult>
  callback to build a new result
Returns IsOk extends true ? Promise<OutResult> : IResultBuild<IsOk, OkType, ErrType>
- Result based on the self value and the value parameter
Example
```
await Ok<number>(2).andThen<IResult<number>>((val) => Promise.resolve(Ok(val + 1))) // Ok<number>(3)
await Err<'broken'>('broken').andThen<IResult<number>>((val) => Promise.resolve(Ok(val + 1))) // Err<'broken'>('broken')
```
- Defined in src/interfaces/IResultImplementation.mts:142

clone

clone(): IResultBuild<IsOk, OkType, ErrType>
Method to clone an result

Returns IResultBuild<IsOk, OkType, ErrType>
- cloned result instance
Example
```
const x = Ok(2);
const y = x.clone(); // Ok(2)
```
- Defined in src/interfaces/IResultImplementation.mts:184

eq

eq(other: IResult): boolean
Method to compare two results
Parameters
- other: IResult
  other result to compare
Returns boolean
true if results are equal
Example
```
Ok<number>(2).eq(Ok<number>(2)) // true
Ok<number>(2).eq(Ok<number>(3)) // false
Err<number>(2).eq(Err<number>(2)) // true
```
- Defined in src/interfaces/IResultImplementation.mts:111

err

err(): IsOk extends false ? ErrType : undefined
Try to get the error, otherwise return undefined

Returns IsOk extends false ? ErrType : undefined
error or undefined
Example
```
Ok<number>(2).err() // undefined
Err<Error>(new Error('broken')).err() // Error('broken')
```
- Defined in src/interfaces/IResultImplementation.mts:68

inspect

inspect(fn: (value: OkType) => void): this
Inspect the result value if Ok
Parameters
- fn: (value: OkType) => void
  function to inspect the value
Returns this
this result instance
Example
```
Ok<number>(2).inspect((value) => console.log('Value:', value)).unwrap() // logs 'Value: 2' and returns 2
```
Since
v1.0.8
- Defined in src/interfaces/IResultImplementation.mts:219

inspectErr

inspectErr(fn: (value: ErrType) => void): this
Inspect the result value if Err
Parameters
- fn: (value: ErrType) => void
  function to inspect the error
Returns this
this result instance
Example
```
Err<Error>(new Error('broken')).inspectErr((err) => console.error('Error:', err)).unwrap() // logs 'Error: Error('broken')' and throws
```
Since
v1.0.8
- Defined in src/interfaces/IResultImplementation.mts:229

isErrAnd

isErrAnd(
callbackFunc: (value: ErrType) => boolean,
): IsOk extends false ? boolean : false
Returns true if the result is Err and callback function returns true for the value inside of Err.
Parameters
- callbackFunc: (value: ErrType) => boolean
Returns IsOk extends false ? boolean : false
true if the result is Err and the callback function returns true for the value inside of Err
Example
```
Err<Error>(new Error('broken')).isErrAnd((err) => err.message === 'broken') // true
Err<Error>(new Error('broken')).isErrAnd((err) => err.message === 'not broken') // false
Ok<number>(2).isErrAnd((err) => err.message === 'broken') // false
```
Since
v1.0.8
- Defined in src/interfaces/IResultImplementation.mts:50

isOkAnd

isOkAnd(
callbackFunc: (value: OkType) => boolean,
): IsOk extends true ? boolean : false
Returns true if the result is Ok and callback function returns true for the value inside of Ok.
Parameters
- callbackFunc: (value: OkType) => boolean
  function to check the value inside of Ok
Returns IsOk extends true ? boolean : false
true if the result is Ok and the callback function returns true for the value inside of Ok
Example
```
Ok<number>(2).isOkAnd((value) => value === 2) // true
Ok<number>(2).isOkAnd((value) => value === 3) // false
Err<Error>(new Error('broken')).isOkAnd((value) => value === 2) // false
```
Since
v1.0.8
- Defined in src/interfaces/IResultImplementation.mts:38

iter

iter(): IterableIterator<
IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : INone,
IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : INone,
>
Iterate over the result value

Returns IterableIterator<
IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : INone,
IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : INone,
>
iterable iterator of the result value
Example
```
Ok<number>(2).iter().next().value; // Ok<number>(2)
Err<Error>(new Error('broken')).iter().next().done; // true (no values to iterate)
```
Since
v1.0.9
- Defined in src/interfaces/IResultImplementation.mts:239

map

map<NewOkType>(
fn: (value: OkType) => NewOkType,
): IsOk extends true ? IOk<NewOkType> : IResultBuild<IsOk, OkType, ErrType>
Map the result value to a new value if Ok
Type Parameters
- NewOkType
Parameters
- fn: (value: OkType) => NewOkType
Returns IsOk extends true ? IOk<NewOkType> : IResultBuild<IsOk, OkType, ErrType>
Example
```
Ok<string, Error>('hello').map((v)=> Buffer.from(v)) // Ok<Buffer, Error>
Err<Error, string>(new Error('broken')).map((v)=> Buffer.from(v)) // Err<Error, Buffer>
```
Since
v1.0.4
- Defined in src/interfaces/IResultImplementation.mts:194

mapErr

mapErr<NewErrType>(
    fn: (value: ErrType) => NewErrType,
): IsOk extends true
    ? IResultBuild<IsOk, OkType, ErrType>
    : IErr<NewErrType>
Map the error value to a new value if Err
Type Parameters
- NewErrType
Parameters
- fn: (value: ErrType) => NewErrType
  function to map the error value
Returns IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : IErr<NewErrType>
new error result instance with mapped error
Example
```
const mapAsTypeErr = (err: Error): TypeError => new TypeError(`Mapped: ${err.message}`);
Err<Error>(new Error('broken')).mapErr(mapAsTypeErr) // Err<TypeError>(new TypeError('Mapped: broken'))
Ok<number>(2).mapErr(mapAsTypeErr); // Ok<number>(2)
// error mapping and logging example
const logErr = (err: Error) => console.error('Error:', err);
Err<Error>(new Error('broken')).mapErr(mapAsTypeErr).inspectErr(logErr);
```
Since
v1.0.4
- Defined in src/interfaces/IResultImplementation.mts:209

ok

ok(): IsOk extends true ? OkType : undefined
Try to get value, otherwise return undefined

Returns IsOk extends true ? OkType : undefined
value or undefined
Example
```
Ok<number>(2).ok() // 2
Err<Error>(new Error('broken')).ok() // undefined
```
- Defined in src/interfaces/IResultImplementation.mts:59

or

or<CompareType>(
    value: IResult<CompareType>,
): IsOk extends true
    ? IResultBuild<IsOk, OkType, ErrType>
    : IResult<CompareType, unknown>
Method to combine two results, if the first result is false return the second result, otherwise return the first result
Type Parameters
- CompareType
Parameters
- value: IResult<CompareType>
  compare value
Returns IsOk extends true
? IResultBuild<IsOk, OkType, ErrType>
: IResult<CompareType, unknown>
- Result based on the self value and the value parameter
Example
```
Err<Error>(new Error('broken')).or(Ok<number>(3)) // Ok<number>(3)
Ok<number>(2).or(Err<Error>(new Error('broken'))) // Ok<number>(2)
Ok<number>(2).or(Ok<number>(3)) // Ok<number>(2)
```
- Defined in src/interfaces/IResultImplementation.mts:154

orElse

orElse<OutResult extends IResult<unknown, unknown>>(
callbackFunc: (value: IsOk extends true ? never : ErrType) => OutResult,
): IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : OutResult
Method to combine two results, if the first result is false use the error to build a new result, otherwise return the first result
Type Parameters
- OutResult extends IResult<unknown, unknown>
Parameters
- callbackFunc: (value: IsOk extends true ? never : ErrType) => OutResult
  callback to build a new result
Returns IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : OutResult
- Result based on the self value and the value parameter
Example
```
Ok<number>(2).orElse<IResult<number>>((errValue) => Ok(errValue * 2)) // Ok<number>(2)
Err<number>(2).orElse<IResult<number>>((errValue) => Ok(errValue * 2)) // Ok<number>(4)
```
- Defined in src/interfaces/IResultImplementation.mts:163

orElsePromise

orElsePromise<OutResult extends IResult<unknown, unknown>>(
    callbackFunc: (
        value: IsOk extends true ? never : ErrType,
    ) => Promise<OutResult>,
): IsOk extends true
    ? IResultBuild<IsOk, OkType, ErrType>
    : Promise<OutResult>
Method to combine two results, if the first result is false use the error to build a new result from Promise, otherwise return the first result
Type Parameters
- OutResult extends IResult<unknown, unknown>
Parameters
- callbackFunc: (value: IsOk extends true ? never : ErrType) => Promise<OutResult>
  callback to build a new result
Returns IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : Promise<OutResult>
- Result based on the self value and the value parameter
Example
```
await Ok<number>(2).orElsePromise<IResult<number>>((errValue) => Promise.resolve(Ok(errValue * 2))) // Ok<number>(2)
await Err<number>(2).orElsePromise<IResult<number>>((errValue) => Promise.resolve(Ok(errValue * 2))) // Ok<number>(4)
```
- Defined in src/interfaces/IResultImplementation.mts:174

toJSON

toJSON(): IsOk extends true ? IJsonOk<OkType> : IJsonErr<ErrType>
Convert result to JSON {$class: 'Result::Ok', value: OkType} or {$class: 'Result::Err', value: ErrType}

Returns IsOk extends true ? IJsonOk<OkType> : IJsonErr<ErrType>
JSON representation of the result
Example
```
Ok<number>(2).toJSON() // {$class: 'Result::Ok', value: 2}
Err<number>(2).toJSON() // {$class: 'Result::Err', value: 2}
```
- Defined in src/interfaces/IResultImplementation.mts:264

toOption

toOption(): IsOk extends true ? ISome<OkType> : INone<never>
Convert result to option and discard the error type

Returns IsOk extends true ? ISome<OkType> : INone<never>
option
Example
```
Ok<number>(2).toOption() // Some<number>(2)
Err<number>(2).toOption() // None<never>()
```
- Defined in src/interfaces/IResultImplementation.mts:248

toString

toString(): IsOk extends true ? `Ok(${string})` : `Err(${string})`
Convert result to string

Returns IsOk extends true ? `Ok(${string})` : `Err(${string})`
string representation of the result
Example
```
Ok<number>(2).toString() // 'Ok(2)'
Err<number>(2).toString() // 'Err(2)'
```
- Defined in src/interfaces/IResultImplementation.mts:256

unwrap

unwrap(): IsOk extends true ? OkType : never
Method to unwrap the value or throw an error.

Note: Error argument/callback was removed in favor of the .errMap((e) => new Error(e.message)).unwrap() method.

Returns IsOk extends true ? OkType : never
Example
```
Ok<number>(2).unwrap() // 2
Err<Error>(new Error('broken')).unwrap() // throws Error('broken')
```
- Defined in src/interfaces/IResultImplementation.mts:77

unwrapOr

unwrapOr<DefaultType>(
defaultValue: DefaultType,
): IsOk extends true ? OkType : DefaultType
Method to unwrap the value or if error return the default value
Type Parameters
- DefaultType
Parameters
- defaultValue: DefaultType
  default value to return if error
Returns IsOk extends true ? OkType : DefaultType
Example
```
Ok<number>(2).unwrapOr(0) // 2
Err<number>(new Error('broken')).unwrapOr(0) // 0
```
- Defined in src/interfaces/IResultImplementation.mts:85

unwrapOrElse

unwrapOrElse<DefaultType>(
callbackFunc: () => DefaultType,
): IsOk extends true ? OkType : DefaultType
Method to unwrap the value or if error return default value from function
Type Parameters
- DefaultType
Parameters
- callbackFunc: () => DefaultType
  function to return default value
Returns IsOk extends true ? OkType : DefaultType
Example
```
Ok<number>(2).unwrapOrElse(() => 0) // 2
Err<number>(new Error('broken')).unwrapOrElse(() => 0) // 0
```
- Defined in src/interfaces/IResultImplementation.mts:93

unwrapOrValueOf

unwrapOrValueOf<ValueType>(
BaseConstructor: ConstructorWithValueOf<ValueType>,
): IsOk extends true ? OkType : ValueType
Method to unwrap the value or if error return default value from constructors valueOf
Type Parameters
- ValueType
Parameters
- BaseConstructor: ConstructorWithValueOf<ValueType>
  constructor to return default value from valueOf
Returns IsOk extends true ? OkType : ValueType
Example
```
Ok<number>(2).unwrapOrValueOf(Number) // 2
Err<Error>(new Error('broken')).unwrapOrValueOf(Number) // 0 (Number.valueOf())
```
- Defined in src/interfaces/IResultImplementation.mts:101

Interface IResultBuild<IsOk, OkType, ErrType>

Since

Type Parameters

Implemented by

Index

Properties

Methods

Properties

isErr

Returns

Example

isOk

Returns

Example

Methods

and

Type Parameters

Parameters

Returns IsOk extends true ? IResult<CompareType, unknown> : IResultBuild<IsOk, OkType, ErrType>

Example

andThen

Type Parameters

Parameters

Returns IsOk extends true ? OutResult : IResultBuild<IsOk, OkType, ErrType>

Example

andThenPromise

Type Parameters

Parameters

Returns IsOk extends true ? Promise<OutResult> : IResultBuild<IsOk, OkType, ErrType>

Example

clone

Returns IResultBuild<IsOk, OkType, ErrType>

Example

eq

Parameters

Returns boolean

Example

err

Returns IsOk extends false ? ErrType : undefined

Example

inspect

Parameters

Returns this

Example

Since

inspectErr

Parameters

Returns this

Example

Since

isErrAnd

Parameters

Returns IsOk extends false ? boolean : false

Example

Since

isOkAnd

Parameters

Returns IsOk extends true ? boolean : false

Example

Since

iter

Returns IterableIterator< IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : INone, IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : INone,>

Example

Since

map

Type Parameters

Parameters

Returns IsOk extends true ? IOk<NewOkType> : IResultBuild<IsOk, OkType, ErrType>

Example

Since

mapErr

Type Parameters

Parameters

Returns IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : IErr<NewErrType>

Example

Since

ok

Returns IsOk extends true ? OkType : undefined

Example

or

Returns IsOk extends true
? IResult<CompareType, unknown>
: IResultBuild<IsOk, OkType, ErrType>

Returns IterableIterator<
IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : INone,
IsOk extends true ? IResultBuild<IsOk, OkType, ErrType> : INone,
>

Returns IsOk extends true
? IResultBuild<IsOk, OkType, ErrType>
: IResult<CompareType, unknown>