fixes #3329

tests/typerel/t2plus.nim

@@ -0,0 +1,22 @@
+discard """
+  output: "2.0"
+"""
+
+{.warning[TypelessParam]: off.}
+
+import future
+
+# bug #3329
+
+proc foldRight[T,U](lst: seq[T], v: U, f: (T, U) -> U): U =
+  result = v
+  for x in lst:
+    result = f(x, result)
+
+proc mean[T: SomeNumber](xs: seq[T]): T =
+  xs.foldRight(0.T, (xBAZ: auto, yBAZ: auto) => xBAZ + yBAZ) / T(xs.len)
+
+when isMainModule:
+  let x = mean(@[1.float, 2, 3])
+  echo x
+