Class ResultExtensions

Extension methods for the Result<T, TErr> type.

Inheritance

object

ResultExtensions

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Namespace: RustyOptions

Assembly: RustyOptions.dll

Syntax

public static class ResultExtensions

Methods

AndThen<T1, T2, TErr>(Result<T1, TErr>, Func<T1, Result<T2, TErr>>)

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

Declaration

public static Result<T2, TErr> AndThen<T1, T2, TErr>(this Result<T1, TErr> self, Func<T1, Result<T2, TErr>> thenFunc) where T1 : notnull where T2 : notnull

Parameters

Type	Name	Description
Result<T1, TErr>	self	The result.
Func<T1, Result<T2, TErr>>	thenFunc	The function to call with the Ok value, if any.

Returns

Type	Description
Result<T2, TErr>	The result of calling thenFunc if the result is Ok, otherwise the Err value of self.

Type Parameters

Name	Description
T1	The Ok type of self.
T2	The Ok type returned by thenFunc.
TErr	The Err type.

And<T1, T2, TErr>(Result<T1, TErr>, Result<T2, TErr>)

Returns other if self is Ok, otherwise returns the Err value of self.

Arguments passed to and are eagerly evaluated; if you are passing the result of a function call, it is recommended to use AndThen<T1, T2, TErr>(Result<T1, TErr>, Func<T1, Result<T2, TErr>>), which is lazily evaluated.

Declaration

public static Result<T2, TErr> And<T1, T2, TErr>(this Result<T1, TErr> self, Result<T2, TErr> other) where T1 : notnull where T2 : notnull

Parameters

Type	Name	Description
Result<T1, TErr>	self	The result.
Result<T2, TErr>	other	The other result.

Returns

Type	Description
Result<T2, TErr>	other if self is Ok, otherwise returns the Err value of self.

Type Parameters

Name	Description
T1	The Ok type of self.
T2	The Ok type of other.
TErr	The Err type.

Flatten<T, TErr>(Result<Result<T, TErr>, TErr>)

Removes one level of nesting from a nested Result<T, TErr>.

Declaration

public static Result<T, TErr> Flatten<T, TErr>(this Result<Result<T, TErr>, TErr> self) where T : notnull

Parameters

Type	Name	Description
Result<Result<T, TErr>, TErr>	self	The result.

Returns

Type	Description
Result<T, TErr>	The inner result.

Type Parameters

Name	Description
T	The Ok type of the result.
TErr	The Err type of the result.

MapErr<T, T1Err, T2Err>(Result<T, T1Err>, Func<T1Err, T2Err>)

Maps a result by applying a function to a contained Err value, leaving an Ok value untouched.

Declaration

public static Result<T, T2Err> MapErr<T, T1Err, T2Err>(this Result<T, T1Err> self, Func<T1Err, T2Err> errMapper) where T : notnull

Parameters

Type	Name	Description
Result<T, T1Err>	self	The result to map.
Func<T1Err, T2Err>	errMapper	The function that converts a contained T1Err value to T2Err.

Returns

Type	Description
Result<T, T2Err>	A result containing the mapped error, or Ok.

Type Parameters

Name	Description
T	The Ok type.
T1Err	The Err type contained by self.
T2Err	The Err type contained by the return value.

Exceptions

Type	Condition
ArgumentNullException	Thrown if errMapper is null.

MapOrElse<T1, T2, TErr>(Result<T1, TErr>, Func<T1, T2>, Func<TErr, T2>)

Maps a Result by applying fallback function defaultFactory to a contained Err value, or function mapper to a contained Ok value.

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

Declaration

public static T2 MapOrElse<T1, T2, TErr>(this Result<T1, TErr> self, Func<T1, T2> mapper, Func<TErr, T2> defaultFactory) where T1 : notnull where T2 : notnull

Parameters

Type	Name	Description
Result<T1, TErr>	self	The result to map.
Func<T1, T2>	mapper	The function that converts a contained Ok value to T2.
Func<TErr, T2>	defaultFactory	The function that converts a contained Err value to T2.

Returns

Type	Description
T2	The mapped value.

Type Parameters

Name	Description
T1	The Ok type contained by self.
T2	The Ok type contained by the return value.
TErr	The Err type.

Exceptions

Type	Condition
ArgumentNullException	Thrown if mapper or defaultFactory is null.

MapOr<T1, T2, TErr>(Result<T1, TErr>, Func<T1, T2>, T2)

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

Arguments passed to MapOr<T1, T2, TErr>(Result<T1, TErr>, Func<T1, T2>, T2) are eagerly evaluated; if you are passing the result of a function call, it is recommended to use MapOrElse<T1, T2, TErr>(Result<T1, TErr>, Func<T1, T2>, Func<TErr, T2>), which is lazily evaluated.

Declaration

public static T2 MapOr<T1, T2, TErr>(this Result<T1, TErr> self, Func<T1, T2> mapper, T2 defaultValue) where T1 : notnull where T2 : notnull

Parameters

Type	Name	Description
Result<T1, TErr>	self	The result to map.
Func<T1, T2>	mapper	The function that converts a contained Ok value to T2.
T2	defaultValue	The default value to return if the result is Err.

Returns

Type	Description
T2	The mapped value, or the default value.

Type Parameters

Name	Description
T1	The Ok type contained by self.
T2	The Ok type contained by the return value.
TErr	The Err type.

Exceptions

Type	Condition
ArgumentNullException	Thrown if mapper is null.

Map<T1, T2, TErr>(Result<T1, TErr>, Func<T1, T2>)

Maps a result by applying a function to a contained Ok value, leaving an Err value untouched.

Declaration

public static Result<T2, TErr> Map<T1, T2, TErr>(this Result<T1, TErr> self, Func<T1, T2> mapper) where T1 : notnull where T2 : notnull

Parameters

Type	Name	Description
Result<T1, TErr>	self	The result to map.
Func<T1, T2>	mapper	The function that converts a contained Ok value to T2.

Returns

Type	Description
Result<T2, TErr>	A result containing the mapped value, or Err.

Type Parameters

Name	Description
T1	The Ok type contained by self.
T2	The Ok type contained by the return value.
TErr	The Err type.

Exceptions

Type	Condition
ArgumentNullException	Thrown if mapper is null.

OrElse<T, T1Err, T2Err>(Result<T, T1Err>, Func<T1Err, Result<T, T2Err>>)

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

Declaration

public static Result<T, T2Err> OrElse<T, T1Err, T2Err>(this Result<T, T1Err> self, Func<T1Err, Result<T, T2Err>> elseFunc) where T : notnull

Parameters

Type	Name	Description
Result<T, T1Err>	self	The result.
Func<T1Err, Result<T, T2Err>>	elseFunc	The function to call with the Err value, if any.

Returns

Type	Description
Result<T, T2Err>	The Ok value of the result, or the result of passing the Err value to elseFunc.

Type Parameters

Name	Description
T	The Ok type of the result.
T1Err	The Err type of self.
T2Err	The Err type returned by elseFunc.

Or<T, T1Err, T2Err>(Result<T, T1Err>, Result<T, T2Err>)

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

Arguments passed to Or<T, T1Err, T2Err>(Result<T, T1Err>, Result<T, T2Err>) are eagerly evaluated; if you are passing the result of a function call, it is recommended to use OrElse<T, T1Err, T2Err>(Result<T, T1Err>, Func<T1Err, Result<T, T2Err>>), which is lazily evaluated.

Declaration

public static Result<T, T2Err> Or<T, T1Err, T2Err>(this Result<T, T1Err> self, Result<T, T2Err> other) where T : notnull

Parameters

Type	Name	Description
Result<T, T1Err>	self	The result.
Result<T, T2Err>	other	The other result.

Returns

Type	Description
Result<T, T2Err>	The Ok value of self, or returns other.

Type Parameters

Name	Description
T	The Ok type of the result.
T1Err	The Err type of self.
T2Err	The Err type of other.

UnwrapOr<T, TErr>(Result<T, TErr>, T)

Returns the contained Ok value, or a provided default.

Arguments passed to UnwrapOr<T, TErr>(Result<T, TErr>, T) are eagerly evaluated; if you are passing the result of a function call, it is recommended to use UnwrapOrElse(Func<TErr, T>), which is lazily evaluated.

Declaration

public static T UnwrapOr<T, TErr>(this Result<T, TErr> self, T defaultValue) where T : notnull

Parameters

Type	Name	Description
Result<T, TErr>	self	The result to unwrap.
T	defaultValue	The default value to return if the result is Err.

Returns

Type	Description
T	The contained Ok value, or the provided default.

Type Parameters

Name	Description
T	The Ok type.
TErr	The Err type.