1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
|
import nativesockets, asyncdispatch, macros
var p = newDispatcher()
var sock = newAsyncNativeSocket()
proc convertReturns(node, retFutureSym: NimNode): NimNode {.compileTime.} =
case node.kind
of nnkReturnStmt:
result = newCall(newIdentNode("complete"), retFutureSym, node[0])
else:
result = node
for i in 0 .. <node.len:
result[i] = convertReturns(node[i], retFutureSym)
macro async2(prc: untyped): untyped =
expectKind(prc, nnkProcDef)
var outerProcBody = newNimNode(nnkStmtList)
# -> var retFuture = newFuture[T]()
var retFutureSym = newIdentNode("retFuture") #genSym(nskVar, "retFuture")
outerProcBody.add(
newVarStmt(retFutureSym,
newCall(
newNimNode(nnkBracketExpr).add(
newIdentNode("newFuture"),
prc[3][0][1])))) # Get type from return type of this proc.
# -> iterator nameIter(): FutureBase {.closure.} = <proc_body>
# Changing this line to: newIdentNode($prc[0].ident & "Iter") # will make it work.
var iteratorNameSym = genSym(nskIterator, $prc[0].ident & "Iter")
assert iteratorNameSym.symKind == nskIterator
#var iteratorNameSym = newIdentNode($prc[0].ident & "Iter")
var procBody = prc[6].convertReturns(retFutureSym)
var closureIterator = newProc(iteratorNameSym, [newIdentNode("FutureBase")],
procBody, nnkIteratorDef)
closureIterator[4] = newNimNode(nnkPragma).add(newIdentNode("closure"))
outerProcBody.add(closureIterator)
# -> var nameIterVar = nameIter
# -> var first = nameIterVar()
var varNameIterSym = newIdentNode($prc[0].ident & "IterVar") #genSym(nskVar, $prc[0].ident & "IterVar")
var varNameIter = newVarStmt(varNameIterSym, iteratorNameSym)
outerProcBody.add varNameIter
var varFirstSym = genSym(nskVar, "first")
assert varFirstSym.symKind == nskVar
var varFirst = newVarStmt(varFirstSym, newCall(varNameIterSym))
outerProcBody.add varFirst
result = prc
# Remove the 'closure' pragma.
for i in 0 .. <result[4].len:
if result[4][i].ident == !"async":
result[4].del(i)
result[6] = outerProcBody
proc readStuff(): Future[string] {.async2.} =
var fut = connect(sock, "irc.freenode.org", Port(6667))
yield fut
var fut2 = recv(sock, 50)
yield fut2
return fut2.read
|