From dda41afe9e5562eddb368ec01f3f76f7206d662f Mon Sep 17 00:00:00 2001
From: Dominik Picheta <dominikpicheta@googlemail.com>
Date: Mon, 12 Oct 2015 23:05:41 +0100
Subject: Implement isReady procedure in threadpool module.

---
 lib/pure/concurrency/threadpool.nim | 11 +++++++++++
 1 file changed, 11 insertions(+)

(limited to 'lib/pure/concurrency')

diff --git a/lib/pure/concurrency/threadpool.nim b/lib/pure/concurrency/threadpool.nim
index 72e744d52..2603835dd 100644
--- a/lib/pure/concurrency/threadpool.nim
+++ b/lib/pure/concurrency/threadpool.nim
@@ -267,6 +267,17 @@ proc awaitAny*(flowVars: openArray[FlowVarBase]): int =
     result = -1
   destroySemaphore(ai.cv)
 
+proc isReady*(fv: FlowVarBase): bool =
+  ## Determines whether the specified ``FlowVarBase``'s value is available.
+  ##
+  ## If ``true`` awaiting ``fv`` will not block.
+  if fv.usesSemaphore and not fv.awaited:
+    acquire(fv.cv.L)
+    result = fv.cv.counter > 0
+    release(fv.cv.L)
+  else:
+    result = true
+
 proc nimArgsPassingDone(p: pointer) {.compilerProc.} =
   let w = cast[ptr Worker](p)
   signal(w.taskStarted)
-- 
cgit 1.4.1-2-gfad0