various bugfixes for generics; added generic sort proc

tests/reject/ttypenoval.nim

@@ -0,0 +1,55 @@
+discard """
+  file: "tambsym.nim"
+  line: 36
+  errormsg: "a type has no value"
+"""
+
+# A min-heap.
+type
+  TNode[T] = tuple[priority: int, data: T]
+
+  TBinHeap[T] = object
+    heap: seq[TNode[T]]
+    last: int
+  
+  PBinHeap[T] = ref TBinHeap[T]
+
+proc newBinHeap*[T](heap: var PBinHeap[T], size: int) =
+  new(heap)
+  heap.last = 0
+  newSeq(heap.heap, size)
+  #newSeq(heap.seq, size)
+ 
+proc parent(elem: int): int {.inline.} =
+  return (elem-1) div 2
+
+proc siftUp[T](heap: PBinHeap[T], elem: int) =
+  var idx = elem
+  while idx != 0:
+    var p = parent(idx)
+    if heap.heap[idx] < heap.heap[p]:
+      swap(heap.heap[idx], heap.heap[p])
+      idx = p
+    else:
+      break
+
+proc add*[T](heap: PBinHeap[T], priority: int, data: T) =
+  var node: TNode[T]
+  node.priority = int
+  node.data = data
+  heap.heap[heap.last] = node
+  siftUp(heap, heap.last)
+  inc(heap.last)
+
+proc print*[T](heap: PBinHeap[T]) =
+  for i in countup(0, heap.last):
+    echo($heap.heap[i])
+
+var
+  heap: PBinHeap[int]
+
+newBinHeap(heap, 256)
+add(heap, 1, 100)
+print(heap)
+
+