refactoring: suggest can import sigmatch for type matching

tests/accept/run/tgenerics1.nim

@@ -0,0 +1,57 @@
+discard """
+  output: "256 100"
+"""
+
+# 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.seq, size)
+
+when false:
+
+  proc parent(elem: int): int =
+      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]:
+              var tmp = heap.heap[idx]
+              heap.heap[idx] = heap.heap[p]
+              heap.heap[p] = tmp
+              idx = p
+          else:
+              break
+
+  proc add*[T](heap: PBinHeap[T], priority: int, data: T) =
+      var node: TNode
+      new(node)
+      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)
+
+