std/asyncfutures

Search:
Source   Edit  

Types

Future[T] = ref object of FutureBase
  ## Stored value
  
Typed future. Source   Edit  
FutureBase = ref object of RootObj
  error*: ref Exception      ## Stored exception
  errorStackTrace*: string
  when not defined(release) or defined(futureLogging):
      ## For debugging purposes only.
    
  
Untyped future. Source   Edit  
FutureError = object of Defect
  cause*: FutureBase
Source   Edit  
FutureVar[T] = distinct Future[T]
Source   Edit  

Consts

NimAsyncContinueSuffix = "NimAsyncContinue"
For internal usage. Do not use. Source   Edit  

Procs

proc `$`(stackTraceEntries: seq[StackTraceEntry]): string {.
    ...raises: [ValueError], tags: [], forbids: [].}
Source   Edit  
proc addCallback(future: FutureBase; cb: proc () {.closure, ...gcsafe.}) {.
    ...raises: [Exception], tags: [RootEffect], forbids: [].}

Adds the callbacks proc to be called when the future completes.

If future has already completed then cb will be called immediately.

Source   Edit  
proc addCallback[T](future: Future[T];
                    cb: proc (future: Future[T]) {.closure, ...gcsafe.})

Adds the callbacks proc to be called when the future completes.

If future has already completed then cb will be called immediately.

Source   Edit  
proc all[T](futs: varargs[Future[T]]): auto

Returns a future which will complete once all futures in futs complete. If the argument is empty, the returned future completes immediately.

If the awaited futures are not Future[void], the returned future will hold the values of all awaited futures in a sequence.

If the awaited futures are Future[void], this proc returns Future[void].

Source   Edit  
proc `and`[T, Y](fut1: Future[T]; fut2: Future[Y]): Future[void]
Returns a future which will complete once both fut1 and fut2 complete. Source   Edit  
proc asyncCheck[T](future: Future[T])

Sets a callback on future which raises an exception if the future finished with an error.

This should be used instead of discard to discard void futures, or use waitFor if you need to wait for the future's completion.

Source   Edit  
proc callback=(future: FutureBase; cb: proc () {.closure, ...gcsafe.}) {.
    ...raises: [Exception], tags: [RootEffect], forbids: [].}

Clears the list of callbacks and sets the callback proc to be called when the future completes.

If future has already completed then cb will be called immediately.

It's recommended to use addCallback or then instead.

Source   Edit  
proc callback=[T](future: Future[T];
                  cb: proc (future: Future[T]) {.closure, ...gcsafe.})

Sets the callback proc to be called when the future completes.

If future has already completed then cb will be called immediately.

Source   Edit  
proc callSoon(cbproc: proc () {....gcsafe.}) {....raises: [Exception],
    tags: [RootEffect], forbids: [].}

Call cbproc "soon".

If async dispatcher is running, cbproc will be executed during next dispatcher tick.

If async dispatcher is not running, cbproc will be executed immediately.

Source   Edit  
proc clean[T](future: FutureVar[T])
Resets the finished status of future. Source   Edit  
proc clearCallbacks(future: FutureBase) {....raises: [], tags: [], forbids: [].}
Source   Edit  
proc complete(future: Future[void]; val = Future[void].default) {.
    ...raises: [Exception], tags: [RootEffect], forbids: [].}
Source   Edit  
proc complete[T](future: Future[T]; val: T)
Completes future with value val. Source   Edit  
proc complete[T](future: FutureVar[T])
Completes a FutureVar. Source   Edit  
proc complete[T](future: FutureVar[T]; val: T)

Completes a FutureVar with value val.

Any previously stored value will be overwritten.

Source   Edit  
proc fail[T](future: Future[T]; error: ref Exception)
Completes future with error. Source   Edit  
proc failed(future: FutureBase): bool {....raises: [], tags: [], forbids: [].}
Determines whether future completed with an error. Source   Edit  
proc finished(future: FutureBase | FutureVar): bool

Determines whether future has completed.

True may indicate an error or a value. Use failed to distinguish.

Source   Edit  
proc getCallSoonProc(): (proc (cbproc: proc ()) {....gcsafe.}) {....raises: [],
    tags: [], forbids: [].}
Get current implementation of callSoon. Source   Edit  
proc mget[T](future: FutureVar[T]): var T

Returns a mutable value stored in future.

Unlike read, this function will not raise an exception if the Future has not been finished.

Source   Edit  
proc newFuture[T](fromProc: string = "unspecified"): owned(Future[T])

Creates a new future.

Specifying fromProc, which is a string specifying the name of the proc that this future belongs to, is a good habit as it helps with debugging.

Source   Edit  
proc newFutureVar[T](fromProc = "unspecified"): owned(FutureVar[T])

Create a new FutureVar. This Future type is ideally suited for situations where you want to avoid unnecessary allocations of Futures.

Specifying fromProc, which is a string specifying the name of the proc that this future belongs to, is a good habit as it helps with debugging.

Source   Edit  
proc `or`[T, Y](fut1: Future[T]; fut2: Future[Y]): Future[void]
Returns a future which will complete once either fut1 or fut2 complete. Source   Edit  
proc read[T](future: Future[T] | FutureVar[T]): T

Retrieves the value of future. Future must be finished otherwise this function will fail with a ValueError exception.

If the result of the future is an error then that error will be raised.

Source   Edit  
proc readError[T](future: Future[T]): ref Exception

Retrieves the exception stored in future.

An ValueError exception will be thrown if no exception exists in the specified Future.

Source   Edit  
proc setCallSoonProc(p: (proc (cbproc: proc ()) {....gcsafe.})) {....raises: [],
    tags: [], forbids: [].}
Change current implementation of callSoon. This is normally called when dispatcher from asyncdispatcher is initialized. Source   Edit