Function extract(case:from:)
@available(
*, deprecated,
message:
"Use case path literal syntax (e.g., '/Root.caseName'), or '(/Root.caseName).extract(from:)'"
)
public func extract<Root, Value>(case embed: @escaping (Value) -> Root, from root: Root) -> Value? Attempts to extract values associated with a given enum case initializer from a given root enum.
extract(case: Result<Int, Error>.success, from: .success(42))
// 42
extract(case: Result<Int, Error>.success, from: .failure(MyError())
// nil
Parameters
| Name | Type | Description |
|---|---|---|
| embed | @escaping (Value) -> Root |
An enum case initializer. |
| root | Root |
A root enum value. |
Returns
Values if they can be extracted from the given enum case initializer and root enum, otherwise nil.
@available(
*, deprecated,
message:
"Use case path literal syntax (e.g., '/Root.caseName'), or '(/Root.caseName).extract(from:)'"
)
public func extract<Root, Value>(case embed: @escaping (Value) -> Root?, from root: Root?) -> Value? Attempts to extract values associated with a given enum case initializer from a given root enum.
extract(case: Result<Int, Error>.success, from: .success(42))
// 42
extract(case: Result<Int, Error>.success, from: .failure(MyError())
// nil
Parameters
| Name | Type | Description |
|---|---|---|
| embed | @escaping (Value) -> Root? |
An enum case initializer. |
| root | Root? |
A root enum value. |
Returns
Values if they can be extracted from the given enum case initializer and root enum, otherwise nil.