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Async File Crawl
Async File Crawl
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|
#light
#time
open System
open System.IO
open System.Threading.Tasks
let private readFileAsync (file:string) (f:byte[] -> 'a) =
async {
// Open stream
use stream = File.OpenRead(file)
// Async read, so we don't block on the thread pool
let! content = stream.AsyncRead(int stream.Length)
// Apply operation on data and return
return f content
} |> Async.StartAsTask
let rec private readDir (dir:string) (f:byte[] -> 'a) =
seq {
// Fire of one async read per file
for file in Directory.GetFiles(dir) do
yield readFileAsync file f
// Spider down through the directory structure
for dir in Directory.GetDirectories(dir) do
yield! readDir dir f
}
let readFilesAsync<'a> (dir:string) (f:byte[] -> 'a) =
let tasks =
readDir dir f
|> Seq.cast<Task>
|> Array.ofSeq
// Wait for all tasks to complete
Task.WaitAll(tasks)
// Return result as a seq
seq {
for task in tasks do
yield (task :?> Task<'a>).Result
}
let result =
readFilesAsync<int> @"C:\Users\Fredrik\Projects\IronJS" (fun b -> b.Length)
|
namespace System
namespace System.IO
namespace System.Threading
namespace System.Threading.Tasks
val private readFileAsync : file:string -> f:(byte [] -> 'a) -> Task<'a>
Full name: Script.readFileAsync
val file : string
Multiple items
val string : value:'T -> string
Full name: Microsoft.FSharp.Core.Operators.string
--------------------
type string = String
Full name: Microsoft.FSharp.Core.string
val f : (byte [] -> 'a)
Multiple items
val byte : value:'T -> byte (requires member op_Explicit)
Full name: Microsoft.FSharp.Core.Operators.byte
--------------------
type byte = Byte
Full name: Microsoft.FSharp.Core.byte
val async : AsyncBuilder
Full name: Microsoft.FSharp.Core.ExtraTopLevelOperators.async
val stream : FileStream
type File =
static member AppendAllLines : path:string * contents:IEnumerable<string> -> unit + 1 overload
static member AppendAllText : path:string * contents:string -> unit + 1 overload
static member AppendText : path:string -> StreamWriter
static member Copy : sourceFileName:string * destFileName:string -> unit + 1 overload
static member Create : path:string -> FileStream + 3 overloads
static member CreateText : path:string -> StreamWriter
static member Decrypt : path:string -> unit
static member Delete : path:string -> unit
static member Encrypt : path:string -> unit
static member Exists : path:string -> bool
...
Full name: System.IO.File
File.OpenRead(path: string) : FileStream
val content : byte []
member Stream.AsyncRead : count:int -> Async<byte []>
member Stream.AsyncRead : buffer:byte [] * ?offset:int * ?count:int -> Async<int>
Multiple items
val int : value:'T -> int (requires member op_Explicit)
Full name: Microsoft.FSharp.Core.Operators.int
--------------------
type int = int32
Full name: Microsoft.FSharp.Core.int
--------------------
type int<'Measure> = int
Full name: Microsoft.FSharp.Core.int<_>
property FileStream.Length: int64
Multiple items
type Async
static member AsBeginEnd : computation:('Arg -> Async<'T>) -> ('Arg * AsyncCallback * obj -> IAsyncResult) * (IAsyncResult -> 'T) * (IAsyncResult -> unit)
static member AwaitEvent : event:IEvent<'Del,'T> * ?cancelAction:(unit -> unit) -> Async<'T> (requires delegate and 'Del :> Delegate)
static member AwaitIAsyncResult : iar:IAsyncResult * ?millisecondsTimeout:int -> Async<bool>
static member AwaitTask : task:Task<'T> -> Async<'T>
static member AwaitWaitHandle : waitHandle:WaitHandle * ?millisecondsTimeout:int -> Async<bool>
static member CancelDefaultToken : unit -> unit
static member Catch : computation:Async<'T> -> Async<Choice<'T,exn>>
static member FromBeginEnd : beginAction:(AsyncCallback * obj -> IAsyncResult) * endAction:(IAsyncResult -> 'T) * ?cancelAction:(unit -> unit) -> Async<'T>
static member FromBeginEnd : arg:'Arg1 * beginAction:('Arg1 * AsyncCallback * obj -> IAsyncResult) * endAction:(IAsyncResult -> 'T) * ?cancelAction:(unit -> unit) -> Async<'T>
static member FromBeginEnd : arg1:'Arg1 * arg2:'Arg2 * beginAction:('Arg1 * 'Arg2 * AsyncCallback * obj -> IAsyncResult) * endAction:(IAsyncResult -> 'T) * ?cancelAction:(unit -> unit) -> Async<'T>
static member FromBeginEnd : arg1:'Arg1 * arg2:'Arg2 * arg3:'Arg3 * beginAction:('Arg1 * 'Arg2 * 'Arg3 * AsyncCallback * obj -> IAsyncResult) * endAction:(IAsyncResult -> 'T) * ?cancelAction:(unit -> unit) -> Async<'T>
static member FromContinuations : callback:(('T -> unit) * (exn -> unit) * (OperationCanceledException -> unit) -> unit) -> Async<'T>
static member Ignore : computation:Async<'T> -> Async<unit>
static member OnCancel : interruption:(unit -> unit) -> Async<IDisposable>
static member Parallel : computations:seq<Async<'T>> -> Async<'T []>
static member RunSynchronously : computation:Async<'T> * ?timeout:int * ?cancellationToken:CancellationToken -> 'T
static member Sleep : millisecondsDueTime:int -> Async<unit>
static member Start : computation:Async<unit> * ?cancellationToken:CancellationToken -> unit
static member StartAsTask : computation:Async<'T> * ?taskCreationOptions:TaskCreationOptions * ?cancellationToken:CancellationToken -> Task<'T>
static member StartChild : computation:Async<'T> * ?millisecondsTimeout:int -> Async<Async<'T>>
static member StartChildAsTask : computation:Async<'T> * ?taskCreationOptions:TaskCreationOptions -> Async<Task<'T>>
static member StartImmediate : computation:Async<unit> * ?cancellationToken:CancellationToken -> unit
static member StartWithContinuations : computation:Async<'T> * continuation:('T -> unit) * exceptionContinuation:(exn -> unit) * cancellationContinuation:(OperationCanceledException -> unit) * ?cancellationToken:CancellationToken -> unit
static member SwitchToContext : syncContext:SynchronizationContext -> Async<unit>
static member SwitchToNewThread : unit -> Async<unit>
static member SwitchToThreadPool : unit -> Async<unit>
static member TryCancelled : computation:Async<'T> * compensation:(OperationCanceledException -> unit) -> Async<'T>
static member CancellationToken : Async<CancellationToken>
static member DefaultCancellationToken : CancellationToken
Full name: Microsoft.FSharp.Control.Async
--------------------
type Async<'T>
Full name: Microsoft.FSharp.Control.Async<_>
static member Async.StartAsTask : computation:Async<'T> * ?taskCreationOptions:TaskCreationOptions * ?cancellationToken:Threading.CancellationToken -> Task<'T>
val private readDir : dir:string -> f:(byte [] -> 'a) -> seq<Task<'a>>
Full name: Script.readDir
val dir : string
Multiple items
val seq : sequence:seq<'T> -> seq<'T>
Full name: Microsoft.FSharp.Core.Operators.seq
--------------------
type seq<'T> = Collections.Generic.IEnumerable<'T>
Full name: Microsoft.FSharp.Collections.seq<_>
type Directory =
static member CreateDirectory : path:string -> DirectoryInfo + 1 overload
static member Delete : path:string -> unit + 1 overload
static member EnumerateDirectories : path:string -> IEnumerable<string> + 2 overloads
static member EnumerateFileSystemEntries : path:string -> IEnumerable<string> + 2 overloads
static member EnumerateFiles : path:string -> IEnumerable<string> + 2 overloads
static member Exists : path:string -> bool
static member GetAccessControl : path:string -> DirectorySecurity + 1 overload
static member GetCreationTime : path:string -> DateTime
static member GetCreationTimeUtc : path:string -> DateTime
static member GetCurrentDirectory : unit -> string
...
Full name: System.IO.Directory
Directory.GetFiles(path: string) : string []
Directory.GetFiles(path: string, searchPattern: string) : string []
Directory.GetFiles(path: string, searchPattern: string, searchOption: SearchOption) : string []
Directory.GetDirectories(path: string) : string []
Directory.GetDirectories(path: string, searchPattern: string) : string []
Directory.GetDirectories(path: string, searchPattern: string, searchOption: SearchOption) : string []
val readFilesAsync : dir:string -> f:(byte [] -> 'a) -> seq<'a>
Full name: Script.readFilesAsync
val tasks : Task []
module Seq
from Microsoft.FSharp.Collections
val cast : source:Collections.IEnumerable -> seq<'T>
Full name: Microsoft.FSharp.Collections.Seq.cast
Multiple items
type Task =
new : action:Action -> Task + 7 overloads
member AsyncState : obj
member ContinueWith : continuationAction:Action<Task> -> Task + 9 overloads
member CreationOptions : TaskCreationOptions
member Dispose : unit -> unit
member Exception : AggregateException
member Id : int
member IsCanceled : bool
member IsCompleted : bool
member IsFaulted : bool
...
Full name: System.Threading.Tasks.Task
--------------------
type Task<'TResult> =
inherit Task
new : function:Func<'TResult> -> Task<'TResult> + 7 overloads
member ContinueWith : continuationAction:Action<Task<'TResult>> -> Task + 9 overloads
member Result : 'TResult with get, set
static member Factory : TaskFactory<'TResult>
Full name: System.Threading.Tasks.Task<_>
--------------------
Task(action: Action) : unit
Task(action: Action, cancellationToken: Threading.CancellationToken) : unit
Task(action: Action, creationOptions: TaskCreationOptions) : unit
Task(action: Action<obj>, state: obj) : unit
Task(action: Action, cancellationToken: Threading.CancellationToken, creationOptions: TaskCreationOptions) : unit
Task(action: Action<obj>, state: obj, cancellationToken: Threading.CancellationToken) : unit
Task(action: Action<obj>, state: obj, creationOptions: TaskCreationOptions) : unit
Task(action: Action<obj>, state: obj, cancellationToken: Threading.CancellationToken, creationOptions: TaskCreationOptions) : unit
--------------------
Task(function: Func<'TResult>) : unit
Task(function: Func<'TResult>, cancellationToken: Threading.CancellationToken) : unit
Task(function: Func<'TResult>, creationOptions: TaskCreationOptions) : unit
Task(function: Func<obj,'TResult>, state: obj) : unit
Task(function: Func<'TResult>, cancellationToken: Threading.CancellationToken, creationOptions: TaskCreationOptions) : unit
Task(function: Func<obj,'TResult>, state: obj, cancellationToken: Threading.CancellationToken) : unit
Task(function: Func<obj,'TResult>, state: obj, creationOptions: TaskCreationOptions) : unit
Task(function: Func<obj,'TResult>, state: obj, cancellationToken: Threading.CancellationToken, creationOptions: TaskCreationOptions) : unit
type Array =
member Clone : unit -> obj
member CopyTo : array:Array * index:int -> unit + 1 overload
member GetEnumerator : unit -> IEnumerator
member GetLength : dimension:int -> int
member GetLongLength : dimension:int -> int64
member GetLowerBound : dimension:int -> int
member GetUpperBound : dimension:int -> int
member GetValue : [<ParamArray>] indices:int[] -> obj + 7 overloads
member Initialize : unit -> unit
member IsFixedSize : bool
...
Full name: System.Array
val ofSeq : source:seq<'T> -> 'T []
Full name: Microsoft.FSharp.Collections.Array.ofSeq
Task.WaitAll([<ParamArray>] tasks: Task []) : unit
Task.WaitAll(tasks: Task [], cancellationToken: Threading.CancellationToken) : unit
Task.WaitAll(tasks: Task [], millisecondsTimeout: int) : bool
Task.WaitAll(tasks: Task [], timeout: TimeSpan) : bool
Task.WaitAll(tasks: Task [], millisecondsTimeout: int, cancellationToken: Threading.CancellationToken) : bool
val task : Task
val result : seq<int>
Full name: Script.result
val b : byte []
property Array.Length: int
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