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+
+import macros
+
+macro enumerate(x: ForLoopStmt): untyped =
+  expectKind x, nnkForStmt
+  # we strip off the first for loop variable and use
+  # it as an integer counter:
+  result = newStmtList()
+  result.add newVarStmt(x[0], newLit(0))
+  var body = x[^1]
+  if body.kind != nnkStmtList:
+    body = newTree(nnkStmtList, body)
+  body.add newCall(bindSym"inc", x[0])
+  var newFor = newTree(nnkForStmt)
+  for i in 1..x.len-3:
+    newFor.add x[i]
+  # transform enumerate(X) to 'X'
+  newFor.add x[^2][1]
+  newFor.add body
+  result.add newFor
+
+proc main*[T](x: T) =
+  {.push experimental: "forLoopMacros".}
+
+  for a, b in enumerate(items([1, 2, 3])):
+    echo a, " ", b
+
+  for a2, b2 in enumerate([1, 2, 3, 5]):
+    echo a2, " ", b2
+  {.pop.}