bugfix: multiple yield statements and loop body vars

tests/accept/run/titer6.nim

@@ -0,0 +1,31 @@
+# Test iterator with more than 1 yield statement
+
+import strutils
+
+iterator tokenize2(s: string, seps: set[char] = Whitespace): tuple[
+  token: string, isSep: bool] =
+  var i = 0
+  while i < s.len:
+    var j = i
+    if s[j] in seps:
+      while j < s.len and s[j] in seps: inc(j)
+      if j > i:
+        yield (copy(s, i, j-1), true)
+    else:
+      while j < s.len and s[j] notin seps: inc(j)
+      if j > i:
+        yield (copy(s, i, j-1), false)
+    i = j
+
+for word, isSep in tokenize2("ta da", whiteSpace):
+  var titer2TestVar = 0 
+  stdout.write(titer2TestVar)
+
+proc wordWrap2(s: string, maxLineWidth = 80, 
+               splitLongWords = true,
+               seps: set[char] = whitespace,
+               newLine = "\n"): string  = 
+  result = ""
+  for word, isSep in tokenize2(s, seps):
+    var w = 0 
+