AsyncBuilder (FSharp.Core) | FSharp.Core

FSharp.Core

AsyncBuilder Type

Namespace: FSharp.Control
Assembly: FSharp.Core.dll
Base Type: obj

The type of the async operator, used to build workflows for asynchronous computations.

Instance members

Instance member	Description
`this.Bind` Full Usage: `this.Bind` Parameters: computation : `Async<'T>` - The computation to provide an unbound result. binder : `'T -> Async<'U>` - The function to bind the result of `computation`. Returns: `Async<'U>` An asynchronous computation that performs a monadic bind on the result of `computation`. Modifiers: inline Type parameters: 'T, 'U	Creates an asynchronous computation that runs `computation`, and when `computation` generates a result `T`, runs `binder res`. A cancellation check is performed when the computation is executed. The existence of this method permits the use of `let!` in the `async { ... }` computation expression syntax. computation : `Async<'T>` The computation to provide an unbound result. binder : `'T -> Async<'U>` The function to bind the result of `computation`. Returns: `Async<'U>` An asynchronous computation that performs a monadic bind on the result of `computation`.
`this.Combine` Full Usage: `this.Combine` Parameters: computation1 : `Async<unit>` - The first part of the sequenced computation. computation2 : `Async<'T>` - The second part of the sequenced computation. Returns: `Async<'T>` An asynchronous computation that runs both of the computations sequentially. Modifiers: inline Type parameters: 'T	Creates an asynchronous computation that first runs `computation1` and then runs `computation2`, returning the result of `computation2`. A cancellation check is performed when the computation is executed. The existence of this method permits the use of expression sequencing in the `async { ... }` computation expression syntax. computation1 : `Async<unit>` The first part of the sequenced computation. computation2 : `Async<'T>` The second part of the sequenced computation. Returns: `Async<'T>` An asynchronous computation that runs both of the computations sequentially.
`this.Delay` Full Usage: `this.Delay` Parameters: generator : `unit -> Async<'T>` - The function to run. Returns: `Async<'T>` An asynchronous computation that runs `generator`.	Creates an asynchronous computation that runs `generator`. A cancellation check is performed when the computation is executed. generator : `unit -> Async<'T>` The function to run. Returns: `Async<'T>` An asynchronous computation that runs `generator`.
`this.For` Full Usage: `this.For` Parameters: sequence : `'T seq` - The sequence to enumerate. body : `'T -> Async<unit>` - A function to take an item from the sequence and create an asynchronous computation. Can be seen as the body of the `for` expression. Returns: `Async<unit>` An asynchronous computation that will enumerate the sequence and run `body` for each element.	Creates an asynchronous computation that enumerates the sequence `seq` on demand and runs `body` for each element. A cancellation check is performed on each iteration of the loop. The existence of this method permits the use of `for` in the `async { ... }` computation expression syntax. sequence : `'T seq` The sequence to enumerate. body : `'T -> Async<unit>` A function to take an item from the sequence and create an asynchronous computation. Can be seen as the body of the `for` expression. Returns: `Async<unit>` An asynchronous computation that will enumerate the sequence and run `body` for each element.
`this.Return` Full Usage: `this.Return` Parameters: value : `'T` - The value to return from the computation. Returns: `Async<'T>` An asynchronous computation that returns `value` when executed. Modifiers: inline Type parameters: 'T	Creates an asynchronous computation that returns the result `v`. A cancellation check is performed when the computation is executed. The existence of this method permits the use of `return` in the `async { ... }` computation expression syntax. value : `'T` The value to return from the computation. Returns: `Async<'T>` An asynchronous computation that returns `value` when executed.
`this.ReturnFrom` Full Usage: `this.ReturnFrom` Parameters: computation : `Async<'T>` - The input computation. Returns: `Async<'T>` The input computation. Modifiers: inline Type parameters: 'T	Delegates to the input computation. The existence of this method permits the use of `return!` in the `async { ... }` computation expression syntax. computation : `Async<'T>` The input computation. Returns: `Async<'T>` The input computation.
`this.TryFinally` Full Usage: `this.TryFinally` Parameters: computation : `Async<'T>` - The input computation. compensation : `unit -> unit` - The action to be run after `computation` completes or raises an exception (including cancellation). Returns: `Async<'T>` An asynchronous computation that executes computation and compensation afterwards or when an exception is raised. Modifiers: inline Type parameters: 'T	Creates an asynchronous computation that runs `computation`. The action `compensation` is executed after `computation` completes, whether `computation` exits normally or by an exception. If `compensation` raises an exception itself the original exception is discarded and the new exception becomes the overall result of the computation. A cancellation check is performed when the computation is executed. The existence of this method permits the use of `try/finally` in the `async { ... }` computation expression syntax. computation : `Async<'T>` The input computation. compensation : `unit -> unit` The action to be run after `computation` completes or raises an exception (including cancellation). Returns: `Async<'T>` An asynchronous computation that executes computation and compensation afterwards or when an exception is raised.
`this.TryWith` Full Usage: `this.TryWith` Parameters: computation : `Async<'T>` - The input computation. catchHandler : `exn -> Async<'T>` - The function to run when `computation` throws an exception. Returns: `Async<'T>` An asynchronous computation that executes `computation` and calls `catchHandler` if an exception is thrown. Modifiers: inline Type parameters: 'T	Creates an asynchronous computation that runs `computation` and returns its result. If an exception happens then `catchHandler(exn)` is called and the resulting computation executed instead. A cancellation check is performed when the computation is executed. The existence of this method permits the use of `try/with` in the `async { ... }` computation expression syntax. computation : `Async<'T>` The input computation. catchHandler : `exn -> Async<'T>` The function to run when `computation` throws an exception. Returns: `Async<'T>` An asynchronous computation that executes `computation` and calls `catchHandler` if an exception is thrown.
`this.Using` Full Usage: `this.Using` Parameters: resource : `'T` - The resource to be used and disposed. binder : `'T -> Async<'U>` - The function that takes the resource and returns an asynchronous computation. Returns: `Async<'U>` An asynchronous computation that binds and eventually disposes `resource`.	Creates an asynchronous computation that runs `binder(resource)`. The action `resource.Dispose()` is executed as this computation yields its result or if the asynchronous computation exits by an exception or by cancellation. A cancellation check is performed when the computation is executed. The existence of this method permits the use of `use` and `use!` in the `async { ... }` computation expression syntax. resource : `'T` The resource to be used and disposed. binder : `'T -> Async<'U>` The function that takes the resource and returns an asynchronous computation. Returns: `Async<'U>` An asynchronous computation that binds and eventually disposes `resource`.
`this.While` Full Usage: `this.While` Parameters: guard : `unit -> bool` - The function to determine when to stop executing `computation`. computation : `Async<unit>` - The function to be executed. Equivalent to the body of a `while` expression. Returns: `Async<unit>` An asynchronous computation that behaves similarly to a while loop when run.	Creates an asynchronous computation that runs `computation` repeatedly until `guard()` becomes false. A cancellation check is performed whenever the computation is executed. The existence of this method permits the use of `while` in the `async { ... }` computation expression syntax. guard : `unit -> bool` The function to determine when to stop executing `computation`. computation : `Async<unit>` The function to be executed. Equivalent to the body of a `while` expression. Returns: `Async<unit>` An asynchronous computation that behaves similarly to a while loop when run.
`this.Zero` Full Usage: `this.Zero` Returns: `Async<unit>` An asynchronous computation that returns `()`.	Creates an asynchronous computation that just returns `()`. A cancellation check is performed when the computation is executed. The existence of this method permits the use of empty `else` branches in the `async { ... }` computation expression syntax. Returns: `Async<unit>` An asynchronous computation that returns `()`.