async macro: general stability improvements [bugfix] (#11787)

1 files changed, 13 insertions, 10 deletions

diff --git a/lib/pure/asyncmacro.nim b/lib/pure/asyncmacro.nim
index 477011285..e9c6f9322 100644
--- a/lib/pure/asyncmacro.nim
+++ b/lib/pure/asyncmacro.nim
@@ -129,7 +129,7 @@ proc processBody(node, retFutureSym: NimNode,
     result.add newNimNode(nnkReturnStmt, node).add(newNilLit())
     return # Don't process the children of this return stmt
   of nnkCommand, nnkCall:
-    if node[0].kind == nnkIdent and node[0].eqIdent("await"):
+    if node[0].eqIdent("await"):
       case node[1].kind
       of nnkIdent, nnkInfix, nnkDotExpr, nnkCall, nnkCommand:
         # await x
@@ -142,7 +142,7 @@ proc processBody(node, retFutureSym: NimNode,
       else:
         error("Invalid node kind in 'await', got: " & $node[1].kind)
     elif node.len > 1 and node[1].kind == nnkCommand and
-         node[1][0].kind == nnkIdent and node[1][0].eqIdent("await"):
+         node[1][0].eqIdent("await"):
       # foo await x
       var newCommand = node
       result.createVar("future" & $node[0].toStrLit, node[1][1], newCommand[1],
@@ -151,7 +151,7 @@ proc processBody(node, retFutureSym: NimNode,
   of nnkVarSection, nnkLetSection:
     case node[0][^1].kind
     of nnkCommand:
-      if node[0][^1][0].kind == nnkIdent and node[0][^1][0].eqIdent("await"):
+      if node[0][^1][0].eqIdent("await"):
         # var x = await y
         var newVarSection = node # TODO: Should this use copyNimNode?
         result.createVar("future" & node[0][0].strVal, node[0][^1][1],
@@ -167,7 +167,7 @@ proc processBody(node, retFutureSym: NimNode,
     else: discard
   of nnkDiscardStmt:
     # discard await x
-    if node[0].kind == nnkCommand and node[0][0].kind == nnkIdent and
+    if node[0].kind == nnkCommand and
           node[0][0].eqIdent("await"):
       var newDiscard = node
       result.createVar("futureDiscard_" & $toStrLit(node[0][1]), node[0][1],
@@ -358,16 +358,15 @@ proc stripAwait(node: NimNode): NimNode =
 
   case node.kind
   of nnkCommand, nnkCall:
-    if node[0].kind == nnkIdent and node[0].eqIdent("await"):
+    if node[0].eqIdent("await"):
       node[0] = emptyNoopSym
-    elif node.len > 1 and node[1].kind == nnkCommand and
-         node[1][0].kind == nnkIdent and node[1][0].eqIdent("await"):
+    elif node.len > 1 and node[1].kind == nnkCommand and node[1][0].eqIdent("await"):
       # foo await x
       node[1][0] = emptyNoopSym
   of nnkVarSection, nnkLetSection:
     case node[0][^1].kind
     of nnkCommand:
-      if node[0][^1][0].kind == nnkIdent and node[0][^1][0].eqIdent("await"):
+      if node[0][^1][0].eqIdent("await"):
         # var x = await y
         node[0][^1][0] = emptyNoopSym
     else: discard
@@ -380,8 +379,7 @@ proc stripAwait(node: NimNode): NimNode =
     else: discard
   of nnkDiscardStmt:
     # discard await x
-    if node[0].kind == nnkCommand and node[0][0].kind == nnkIdent and
-          node[0][0].eqIdent("await"):
+    if node[0].kind == nnkCommand and node[0][0].eqIdent("await"):
       node[0][0] = emptyNoopSym
   else: discard
 
@@ -441,3 +439,8 @@ macro multisync*(prc: untyped): untyped =
   result = newStmtList()
   result.add(asyncSingleProc(asyncPrc))
   result.add(sync)
+
+proc await*[T](x: T) =
+  ## The 'await' keyword is also defined here for technical
+  ## reasons. (Generic symbol lookup prepass.)
+  {.error: "Await only available within .async".}