ValueTask (FSharp.Core) | FSharp.Core

FSharp.Core

ValueTask Module

Namespace: FSharp.Control
Assembly: FSharp.Core.dll

Contains camelCase module-level functions for ValueTask computations.

Functions and values

Function or value	Description
`ValueTask.bind binder task` Full Usage: `ValueTask.bind binder task` Parameters: binder : `'T -> ValueTask<'U>` - A function that takes the result of the value task and returns a new value task. task : `ValueTask<'T>` - The input value task. Returns: `ValueTask<'U>` A value task that performs a monadic bind on the result of `task`. Modifiers: inline Type parameters: 'T, 'U	Creates a value task that passes the result of the given value task to the binder function. binder : `'T -> ValueTask<'U>` A function that takes the result of the value task and returns a new value task. task : `ValueTask<'T>` The input value task. Returns: `ValueTask<'U>` A value task that performs a monadic bind on the result of `task`. Example `let vt = ValueTask.result 21 \|> ValueTask.bind (fun x -> ValueTask.result (x * 2)) vt.Result // evaluates to 42` val vt: obj
`ValueTask.catch task` Full Usage: `ValueTask.catch task` Parameters: task : `ValueTask<'T>` - The input `ValueTask`. Returns: `ValueTask<Result<'T, exn>>` A `ValueTask` that yields a `Result`: `Ok` with the outcome on success, or `Error` with the exception on failure. Propagates the underlying cancellation exception when `task` is canceled. Type parameters: 'T	Creates a `ValueTask` that reifies the outcome of the given `ValueTask` as a `Result`: `Ok` on success, `Error` on failure, so faults become values. Cancellation still propagates. `OperationCanceledException` and derived types such as `TaskCanceledException` propagate unchanged (and the task remains Canceled) in order to maintain cancellation semantics. task : `ValueTask<'T>` The input `ValueTask`. Returns: `ValueTask<Result<'T, exn>>` A `ValueTask` that yields a `Result`: `Ok` with the outcome on success, or `Error` with the exception on failure. Propagates the underlying cancellation exception when `task` is canceled. Example `let safeDiv x y = task { return x / y } \|> ValueTask.ofTask \|> ValueTask.catch (safeDiv 10 2).Result // evaluates to Ok 5 (safeDiv 10 0).Result // evaluates to Error (DivideByZeroException ...)` val safeDiv: x: int -> y: int -> 'a val x: int val y: int val task: TaskBuilder Multiple items module Result from Microsoft.FSharp.Core -------------------- type Result<'T,'TError> = \| Ok of ResultValue: 'T \| Error of ErrorValue: 'TError
`ValueTask.catchWith handler task` Full Usage: `ValueTask.catchWith handler task` Parameters: handler : `exn -> 'T` - A function to handle (non-cancellation) exceptions, yielding a recovery value based on the exception. Any exception thrown by `handler` will propagate. task : `ValueTask<'T>` - The input `ValueTask`. Returns: `ValueTask<'T>` A `ValueTask` that yields the result of `task` on success, or `handler exn` on failure. Propagates the underlying cancellation exception when `task` is canceled. Modifiers: inline Type parameters: 'T	Creates a `ValueTask` that yields the original result on success, or the result of `handler exn` for non-cancellation exceptions. `OperationCanceledException` and derived types such as `TaskCanceledException` propagate unchanged (and the task remains Canceled) in order to maintain cancellation semantics, and therefore are never passed to `handler`. handler : `exn -> 'T` A function to handle (non-cancellation) exceptions, yielding a recovery value based on the exception. Any exception thrown by `handler` will propagate. task : `ValueTask<'T>` The input `ValueTask`. Returns: `ValueTask<'T>` A `ValueTask` that yields the result of `task` on success, or `handler exn` on failure. Propagates the underlying cancellation exception when `task` is canceled. Example `let safeDiv x y = task { return x / y } \|> ValueTask.ofTask \|> ValueTask.catchWith (fun _ -> 0) (safeDiv 10 0).Result // evaluates to 0` val safeDiv: x: int -> y: int -> 'a val x: int val y: int val task: TaskBuilder Multiple items module Result from Microsoft.FSharp.Core -------------------- type Result<'T,'TError> = \| Ok of ResultValue: 'T \| Error of ErrorValue: 'TError
`ValueTask.empty` Full Usage: `ValueTask.empty` Returns: `ValueTask<unit>`	A completed value task that returns `unit`. Returns: `ValueTask<unit>` Example `ValueTask.empty.Result // evaluates to ()`
`ValueTask.ignore task` Full Usage: `ValueTask.ignore task` Parameters: task : `ValueTask<'T>` - The input value task. Returns: `ValueTask<unit>` A value task that is equivalent to the input value task, but disregards the result. Modifiers: inline Type parameters: 'T	Creates a value task that runs the given value task and ignores its result. When the value task is already synchronously complete, this avoids allocating a `Task`. task : `ValueTask<'T>` The input value task. Returns: `ValueTask<unit>` A value task that is equivalent to the input value task, but disregards the result. Example `let vt : ValueTask<unit> = ValueTask.result 42 \|> ValueTask.ignore<int> vt.Result // evaluates to ()` val vt: obj type unit = Unit Multiple items val int: value: 'T -> int (requires member op_Explicit) -------------------- type int = int32 -------------------- type int<'Measure> = int
`ValueTask.map mapping task` Full Usage: `ValueTask.map mapping task` Parameters: mapping : `'T -> 'U` - The function to apply to the result. task : `ValueTask<'T>` - The input value task. Returns: `ValueTask<'U>` A value task that applies `mapping` to the result of `task`. Modifiers: inline Type parameters: 'T, 'U	Creates a value task that applies the mapping function to the result of the given value task. mapping : `'T -> 'U` The function to apply to the result. task : `ValueTask<'T>` The input value task. Returns: `ValueTask<'U>` A value task that applies `mapping` to the result of `task`. Example `let vt = ValueTask.result 21 \|> ValueTask.map (fun x -> x * 2) vt.Result // evaluates to 42` val vt: obj
`ValueTask.ofTask task` Full Usage: `ValueTask.ofTask task` Parameters: task : `Task<'T>` - The input task. Returns: `ValueTask<'T>` A value task equivalent to the given task. Modifiers: inline Type parameters: 'T	Converts a Task to a ValueTask. task : `Task<'T>` The input task. Returns: `ValueTask<'T>` A value task equivalent to the given task. Example `let t = Task.FromResult 42 let vt = ValueTask.ofTask t vt.Result // evaluates to 42` val t: obj val vt: obj
`ValueTask.result value` Full Usage: `ValueTask.result value` Parameters: value : `'T` - The value to return. Returns: `ValueTask<'T>` A completed value task that returns `value`. Modifiers: inline Type parameters: 'T	Creates a value task that returns the given value. value : `'T` The value to return. Returns: `ValueTask<'T>` A completed value task that returns `value`. Example `let vt = ValueTask.result 42 vt.Result // evaluates to 42` val vt: obj