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Interface: IResult<T, E>

@sapphire/result.IResult

A type used to express computations that can fail, it can be used for returning and propagating errors. This is a type union with the variants Ok(T), representing success and containing a value, and Err(E), representing error and containing an error value.

Typeparam

T The result's type.

Typeparam

E The error's type.

See

https://doc.rust-lang.org/std/result/index.html

Type parameters​

Name
T
E

Implemented by​

Methods​

[iterator]​

▸ [iterator](): Generator<T, any, unknown>

Returns an iterator over the possibly contained value.

The iterator yields one value if the result is Ok, otherwise none.

Example

const x = ok(7);
for (const value of x) {
  console.log(value);
}
// Logs 7

Example

const x = err('Nothing!');
for (const value of x) {
  console.log(value);
}
// Doesn't log

See

Returns​

Generator<T, any, unknown>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:863

and​

▸ and<U>(result): Result<U, E>

Returns result if the result is Ok, otherwise returns the Err value of itself.

Example

const x: Result<number, string> = ok(2);
const y: Result<string, string> = err('Late error');
assert.equal(x.and(y), err('Late error'));

Example

const x: Result<number, string> = err('Early error');
const y: Result<string, string> = err('Late error');
assert.equal(x.and(y), err('Early error'));

Example

const x: Result<number, string> = ok(2);
const y: Result<string, string> = ok('Hello');
assert.equal(x.and(y), ok('Hello'));

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.and

Type parameters​

Name
U

Parameters​

NameTypeDescription
resultResult<U, E>The result to check.

Returns​

Result<U, E>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:601

andThen​

▸ andThen<U>(cb): Result<U, E>

Calls cb if the result is Ok, otherwise returns the Err value of self.

This function can be used for control flow based on Result values.

Example

function fractionOf4(value: number) {
  return value === 0 ? err('overflowed') : ok(4 / value);
}

assert.equal(ok(2).andThen(fractionOf4), ok(4));
assert.equal(ok(0).andThen(fractionOf4), err('overflowed'));
assert.equal(err('not a number').andThen(fractionOf4), err('not a number'));

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.and_then

Type parameters​

Name
U

Parameters​

NameTypeDescription
cb(value: T) => Result<U, E>The predicate.

Returns​

Result<U, E>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:622

contains​

▸ contains(value): boolean

Returns true if the result is an Ok and the given value strict equals it.

Example

const x: Result<number, string> = ok(2);
assert.equal(x.contains(2), true);

Example

const x: Result<number, string> = ok(3);
assert.equal(x.contains(2), false);

Example

const x: Result<number, string> = err('Some error message');
assert.equal(x.contains(2), false);

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.contains

Parameters​

NameTypeDescription
valueTThe value to compare.

Returns​

boolean

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:703

containsErr​

▸ containsErr(error): boolean

Returns true if the result is an Err and the given error strict equals it.

Example

const x: Result<number, string> = ok(2);
assert.equal(x.containsErr('Some error message'), false);

Example

const x: Result<number, string> = err('Some error message');
assert.equal(x.containsErr('Some error message'), true);

Example

const x: Result<number, string> = err('Some other error message');
assert.equal(x.containsErr('Some error message'), false);

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.contains_err

Parameters​

NameTypeDescription
errorEThe error to compare.

Returns​

boolean

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:727

eq​

▸ eq(other): boolean

Checks whether or not other equals with self.

See

https://doc.rust-lang.org/std/cmp/trait.PartialEq.html#tymethod.eq

Parameters​

NameTypeDescription
otherResult<T, E>The other result to compare.

Returns​

boolean

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:805

err​

▸ err(): Option<E>

Converts from Result<T, E> to Option<E>.

Converts itself into an Option<E>, and discarding the successful value, if any.

Example

const x: Result<number, string> = ok(2);
assert.equal(x.err(), none);

Example

const x: Result<number, string> = err('Some error message');
assert.equal(x.err(), 'Some error message');

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.err

Returns​

Option<E>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:139

expect​

▸ expect(message): T

Returns the contained Ok value.

If the value is an Err, it throws a ResultError with the given message and the content of the Err.

Example

const x = ok(2);
assert.equal(x.expect('Whoops!'), 2);

Example

const x = err('Emergency failure');
assert.throws(() => x.expect('Whoops!'), {
  name: 'ResultError',
  message: 'Whoops',
  value: 'Emergency failure'
});

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.expect

Parameters​

NameTypeDescription
messagestringThe message for the error.

Returns​

T

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:419

expectErr​

▸ expectErr(message): E

Returns the contained Err value.

If the value is an Ok, it throws a ResultError with the given message and the content of the Ok.

Example

const x = ok(2);
assert.throws(() => x.expectErr('Whoops!'), {
  name: 'ResultError',
  message: 'Whoops',
  value: 2
});

Example

const x = err('Emergency failure');
assert.equal(x.expectErr('Whoops!'), 'Emergency failure');

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.expect_err

Parameters​

NameTypeDescription
messagestringThe message for the error.

Returns​

E

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:444

flatten​

▸ flatten<IT>(this): Result<IT, E>

Converts from Result<Result<T, E>, E> to Result<T, E>.

Example

const x: Result<Result<string, number>, number> = ok(ok('Hello'));
assert.equal(x.flatten(), ok('Hello'));

Example

const x: Result<Result<string, number>, number> = ok(err(6));
assert.equal(x.flatten(), err(6));

Example

const x: Result<Result<string, number>, number> = err(6);
assert.equal(x.flatten(), err(6));

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.flatten

Type parameters​

Name
IT

Parameters​

NameType
thisResult<Result<IT, E>, E>

Returns​

Result<IT, E>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:766

inspect​

▸ inspect(cb): IResult<T, E>

Calls the provided closure with a reference to the contained value (if Ok).

Seealso

inspectAsync for the awaitable version.

Example

ok(2).inspect(console.log);
// Logs: 2

Example

err('Some error message').inspect(console.log);
// Doesn't log

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.inspect

Parameters​

NameTypeDescription
cb(value: T) => voidThe predicate.

Returns​

IResult<T, E>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:308

inspectAsync​

▸ inspectAsync(cb): Promise<IResult<T, E>>

Calls the provided closure with a reference to the contained value (if Ok) and awaits it.

Seealso

inspect for the sync version.

Example

await ok(2).inspectAsync(console.log);
// Logs: 2

Example

await err('Some error message').inspectAsync(console.log);
// Doesn't log

Note

This is an extension not supported in Rust

Parameters​

NameTypeDescription
cb(value: T) => Awaitable<void>The predicate.

Returns​

Promise<IResult<T, E>>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:328

inspectErr​

▸ inspectErr(cb): IResult<T, E>

Calls the provided closure with a reference to the contained error (if Err).

Seealso

inspectErrAsync for the awaitable version.

Example

ok(2).inspectErr(console.log);
// Doesn't log

Example

err('Some error message').inspectErr(console.log);
// Logs: Some error message

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.inspect_err

Parameters​

NameTypeDescription
cb(error: E) => voidThe predicate.

Returns​

IResult<T, E>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:348

inspectErrAsync​

▸ inspectErrAsync(cb): Promise<IResult<T, E>>

Calls the provided closure with a reference to the contained error (if Err) and awaits it.

Seealso

inspectErr for the sync version.

Example

await ok(2).inspectErrAsync(console.log);
// Doesn't log

Example

await err('Some error message').inspectErrAsync(console.log);
// Logs: Some error message

Note

This is an extension not supported in Rust

Parameters​

NameTypeDescription
cb(error: E) => Awaitable<void>The predicate.

Returns​

Promise<IResult<T, E>>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:368

intoOkOrErr​

▸ intoOkOrErr(): T | E

Returns the Ok value if self is Ok, and the Err value if self is Err.

Example

let x: Result<number, number> = ok(3);
assert.equal(x.intoOkOrErr(), 3);

Example

let x: Result<number, number> = err(4);
assert.equal(x.intoOkOrErr(), 4);

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.into_ok_or_err

Returns​

T | E

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:784

intoPromise​

▸ intoPromise(): Promise<Result<Awaited<T>, Awaited<E>>>

Returns a Promise object with the awaited value (if Ok) or the awaited error (if Err).

Example

let x = ok(Promise.resolve(3));
assert.equal(await x.intoPromise(), ok(3));

Note

This is an extension not supported in Rust

Returns​

Promise<Result<Awaited<T>, Awaited<E>>>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:797

isErr​

▸ isErr(): this is Err<E>

Returns true if the result is Err.

Example

const x = ok(-3);
assert.equal(x.isErr(), false);

Example

const x = err('Some error message');
assert.equal(x.isErr(), true);

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.is_err

Returns​

this is Err<E>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:75

isErrAnd​

▸ isErrAnd<R>(cb): this is Err<E> & R

Returns true if the result is Err and the value inside of it matches a predicate.

Example

const x = ok(2);
assert.equal(x.isErrAnd((error) => error instanceof TypeError), false);

Example

const x = err(new Error('Some error message'));
assert.equal(x.isErrAnd((error) => error instanceof TypeError), false);

Example

const x = err(new TypeError('Some error message'));
assert.equal(x.isErrAnd((error) => error instanceof TypeError), true);

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.is_err_and

Type parameters​

NameType
Rextends boolean

Parameters​

NameTypeDescription
cb(error: E) => RThe predicate.

Returns​

this is Err<E> & R

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:99

isOk​

▸ isOk(): this is Ok<T>

Returns true if the result is Ok.

Example

const x = ok(-3);
assert.equal(x.isOk(), true);

Example

const x = err('Some error message');
assert.equal(x.isOk(), false);

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.is_ok

Returns​

this is Ok<T>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:34

isOkAnd​

▸ isOkAnd<R>(cb): this is Ok<T> & R

Returns true if the result is Ok and the value inside of it matches a predicate.

Example

const x = ok(2);
assert.equal(x.isOkAnd((value) => value > 1), true);

Example

const x = ok(0);
assert.equal(x.isOkAnd((value) => value > 1), false);

Example

const x = err('Some error message');
assert.equal(x.isOkAnd((value) => value > 1), false);

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.is_ok_and

Type parameters​

NameType
Rextends boolean

Parameters​

NameType
cb(value: T) => R

Returns​

this is Ok<T> & R

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:57

iter​

▸ iter(): Generator<T, any, unknown>

Returns an iterator over the possibly contained value.

The iterator yields one value if the result is Ok, otherwise none.

Example

const x = ok(7);
for (const value of x.iter()) {
  console.log(value);
}
// Logs 7

Example

const x = err('Nothing!');
for (const value of x.iter()) {
  console.log(value);
}
// Doesn't log

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.iter

Returns​

Generator<T, any, unknown>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:394

map​

▸ map<U>(cb): Result<U, E>

Maps a Result<T, E> to Result<U, E> by applying a function to a contained Ok value, leaving an Err value untouched.

Example

const x: Result<number, string> = ok(2);
assert.equal(x.map((value) => value * 2), ok(4));

Example

const x: Result<number, string> = err('Some error message');
assert.equal(x.map((value) => value * 2), err('Some error message'));

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.map

Type parameters​

Name
U

Parameters​

NameTypeDescription
cb(value: T) => UThe predicate.

Returns​

Result<U, E>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:159

mapErr​

▸ mapErr<F>(cb): Result<T, F>

Maps a Result<T, E> to Result<T, F> by applying a function to a contained Err value, leaving an Ok value untouched.

This function can be used to pass through a successful result while handling an error.

Example

const x: Result<number, Error> = ok(2);
assert.equal(x.mapErr((error) => error.message), ok(2));

Example

const x: Result<number, Error> = err(new Error('Some error message'));
assert.equal(x.mapErr((error) => error.message), err('Some error message'));

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.map_err

Type parameters​

Name
F

Parameters​

NameTypeDescription
cb(error: E) => FThe predicate.

Returns​

Result<T, F>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:258

mapErrInto​

▸ mapErrInto<IT, IE>(cb): Result<T | IT, IE>

Maps a Result<T, E> to Result<T, F> by applying a function to a contained Err value, leaving an Ok value untouched.

This function can be used to pass through a successful result while handling an error.

Unlike mapErr, this method does not wrap the returned value inside Err, but instead, it returns the returned value.

Example

const x: Result<number, Error> = ok(2);
assert.equal(x.mapErrInto((error) => err(error.message)), ok(2));

Example

const x: Result<number, Error> = err(new Error('Some error message'));
assert.equal(x.mapErrInto((error) => err(error.message)), err('Some error message'));

Example

const x: Result<number, Error> = err(new Error('Some error message'));
assert.equal(x.mapErrInto((error) => ok(4)), ok(4));

Note

This is an extension not supported in Rust

Type parameters​

Name
IT
IE

Parameters​

NameTypeDescription
cb(error: E) => Result<IT, IE>The predicate.

Returns​

Result<T | IT, IE>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:288

mapInto​

▸ mapInto<IT, IE>(cb): Result<IT, E | IE>

Maps a Result<T, E> to Result<T, F> by applying a function to a contained Ok value, leaving an Err value untouched.

Unlike map, this method does not wrap the returned value inside Ok, but instead, it returns the returned value.

Example

const x: Result<number, string> = ok(2);
assert.equal(x.mapInto((value) => ok(value * value)), ok(4));

Example

const x: Result<number, string> = ok(0);
assert.equal(
  x.mapInto((value) => (value === 0 ? err('zero is not divisible') : ok(1 / value))),
  err('zero is not divisible')
);

Example

const x: Result<number, string> = err('Some error message');
assert.equal(x.mapInto((value) => ok(4)), err('Some error message'));

Note

This is an extension not supported in Rust

Type parameters​

Name
IT
IE

Parameters​

NameTypeDescription
cb(value: T) => Result<IT, IE>The predicate.

Returns​

Result<IT, E | IE>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:190

mapOr​

▸ mapOr<U>(defaultValue, cb): U

Returns the provided default (if Err), or applies a function to the contained value (if Ok),

Arguments passed to mapOr are eagerly evaluated; if you are passing the result of a function call, it is recommended to use mapOrElse, which is lazily evaluated.

Example

const x = ok('hello');
assert.equal(x.mapOr(42, (value) => value.length), 5);

Example

const x = err('Some error message');
assert.equal(x.mapOr(42, (value) => value.length), 42);

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.map_or

Type parameters​

Name
U

Parameters​

NameTypeDescription
defaultValueUThe default value to use.
cb(value: T) => UThe predicate.

Returns​

U

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:213

mapOrElse​

▸ mapOrElse<U>(op, cb): U

Maps a Result<T, E> to U by applying fallback function default to a contained Err value, or function cb to a contained Ok value.

This function can be used to unpack a successful result while handling an error.

Example

const x: Result<string, string> = ok('hello');
assert.equal(x.mapOrElse((error) => error.length, (value) => value.length), 5);

Example

const x: Result<string, string> = err('Some error message');
assert.equal(x.mapOrElse((error) => error.length, (value) => value.length), 18);

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.map_or_else

Type parameters​

Name
U

Parameters​

NameTypeDescription
op(error: E) => UThe predicate that is run on Err.
cb(value: T) => UThe predicate that is run on Ok.

Returns​

U

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:236

match​

▸ match<OkValue, ErrValue>(branches): OkValue | ErrValue

Runs ok function if self is Ok, otherwise runs err function.

Example

const result = ok(4).match({
  ok: (v) => v,
  err: () => 0
});
assert.equal(result, 4);

Example

const result = err('Hello').match({
  ok: (v) => v,
  err: () => 0
});
assert.equal(result, 0);

Type parameters​

Name
OkValue
ErrValue

Parameters​

NameTypeDescription
branchesObjectThe branches to match.
branches.err(error: E) => ErrValue-
branches.ok(value: T) => OkValue-

Returns​

OkValue | ErrValue

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:836

ne​

▸ ne(other): boolean

Checks whether or not other doesn't equal with self.

See

https://doc.rust-lang.org/std/cmp/trait.PartialEq.html#method.ne

Parameters​

NameTypeDescription
otherResult<T, E>The other result to compare.

Returns​

boolean

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:813

ok​

▸ ok(): Option<T>

Converts from Result<T, E> to Option<T>.

Converts itself into an Option<T>, and discarding the error, if any.

Example

const x: Result<number, string> = ok(2);
assert.equal(x.ok(), some(2));

Example

const x: Result<number, string> = err('Some error message');
assert.equal(x.ok(), none);

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.ok

Returns​

Option<T>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:119

or​

▸ or<F>(result): Result<T, F>

Return result if the result is Err, otherwise returns the Ok value of self.

Arguments passed to or are eagerly evaluated; if you are passing the result of a function call, it is recommended to use orElse, which is lazily evaluated.

Example

const x: Result<number, string> = ok(2);
const y: Result<number, string> = err('Late error');
assert.equal(x.or(y), ok(2));

Example

const x: Result<number, string> = err('Early error');
const y: Result<number, string> = ok(2);
assert.equal(x.or(y), ok(2));

Example

const x: Result<number, string> = err('Early error');
const y: Result<number, string> = err('Late error');
assert.equal(x.or(y), err('Late error'));

Example

const x: Result<number, string> = ok(2);
const y: Result<number, string> = ok(100);
assert.equal(x.or(y), ok(2));

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.or

Type parameters​

Name
F

Parameters​

NameTypeDescription
resultResult<T, F>The result to check.

Returns​

Result<T, F>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:658

orElse​

▸ orElse<F>(cb): Result<T, F>

Calls cb if the result is Err, otherwise returns the Ok value of self.

This function can be used for control flow based on result values.

Example

const square = (x: number): Result<number, string> => ok(x * x);
const wrapErr = (x: number): Result<number, string> => err(x);

assert.equal(ok(2).orElse(square).orElse(square), ok(2));
assert.equal(ok(2).orElse(wrapErr).orElse(square), ok(2));
assert.equal(err(3).orElse(square).orElse(wrapErr), ok(9));
assert.equal(err(3).orElse(wrapErr).orElse(wrapErr), err(3));

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.or_else

Type parameters​

Name
F

Parameters​

NameTypeDescription
cb(error: E) => Result<T, F>The predicate.

Returns​

Result<T, F>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:679

transpose​

▸ transpose<IT>(this): Option<Result<IT, E>>

Transposes a Result of an Option into an Option of a Result.

ok(none) will be mapped to none. ok(some(v)) and err(e) will be mapped to some(ok(v)) and some(err(e)).

Example

const x: Result<Option<number>, Error> = ok(some(5));
const y: Option<Result<number, Error>> = some(ok(5));
assert.equal(x.transpose(), y);

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.transpose

Type parameters​

Name
IT

Parameters​

NameType
thisResult<Option<IT>, E>

Returns​

Option<Result<IT, E>>

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:743

unwrap​

▸ unwrap(): T

Returns the contained Ok value.

If the value is an Err, it throws a ResultError with the message, and the content of the Err.

Seealso

unwrapOr

Seealso

unwrapOrElse

Seealso

unwrapErr

Seealso

unwrapRaw

Example

const x = ok(2);
assert.equal(x.unwrap(), 2);

Example

const x = err('Emergency failure');
assert.throws(() => x.unwrap(), {
  name: 'ResultError',
  message: 'Unwrap failed',
  value: 'Emergency failure'
});

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.unwrap

Returns​

T

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:472

unwrapErr​

▸ unwrapErr(): E

Returns the contained Err value.

If the value is an Ok, it throws a ResultError with the message, and the content of the Ok.

Seealso

unwrap

Seealso

unwrapOr

Seealso

unwrapOrElse

Seealso

unwrapRaw

Example

const x = ok(2);
assert.throws(() => x.unwrapErr(), {
  name: 'ResultError',
  message: 'Unwrap failed',
  value: 2
});

Example

const x = err('Emergency failure');
assert.equal(x.unwrapErr(), 'Emergency failure');

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.unwrap_err

Returns​

E

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:500

unwrapOr​

▸ unwrapOr<V>(defaultValue): T | V

Returns the contained Ok value or the provided default.

Arguments passed to unwrapOr are eagerly evaluated; if you are passing the result of a function call, it is recommended to use unwrapOrElse, which is lazily evaluated.

Seealso

unwrap

Seealso

unwrapOrElse

Seealso

unwrapErr

Seealso

unwrapRaw

Example

const x: Result<number, string> = ok(9);
assert.equal(x.unwrapOr(2), 9);

Example

const x: Result<number, string> = err('Error');
assert.equal(x.unwrapOr(2), 2);

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.unwrap_or

Type parameters​

Name
V

Parameters​

NameTypeDescription
defaultValueVThe default value.

Returns​

T | V

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:527

unwrapOrElse​

▸ unwrapOrElse<V>(op): T | V

Returns the contained Ok value or computes it from a closure.

Seealso

unwrap

Seealso

unwrapOr

Seealso

unwrapErr

Seealso

unwrapRaw

Example

const count = (x: string) => x.length;

assert.equal(ok(2).unwrapOrElse(count), 2);
assert.equal(err('hello').unwrapOrElse(count), 5);

See

https://doc.rust-lang.org/std/result/enum.Result.html#method.unwrap_or_else

Type parameters​

Name
V

Parameters​

NameTypeDescription
op(error: E) => VThe predicate.

Returns​

T | V

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:548

unwrapRaw​

▸ unwrapRaw(): T

Returns the contained Ok value.

If the value is an Err, it throws the contained error.

Seealso

unwrap

Seealso

unwrapOr

Seealso

unwrapOrElse

Seealso

unwrapErr

Example

const x = ok(2);
assert.equal(x.unwrapRaw(), 2);

Example

const x = err('Emergency failure');
assert.throws(() => x.unwrapRaw(), {
  name: 'Error',
  message: 'Unwrap failed',
  value: 'Emergency failure'
});

Returns​

T

Defined in​

projects/utilities/packages/result/src/lib/Result/IResult.ts:574