implemented refs draft

experiments/refs/demo.nim

@@ -0,0 +1,39 @@
+include karaxprelude
+import random
+
+var
+  modelData = @[5, 2, 4]
+
+  refA = VNodeRef()
+  refB = VNodeRef()
+  refSeq = newSeq[VNodeRef]()
+
+proc onClick(ev: Event, n: VNode) =
+  kout(refA)
+  kout(refB)
+  kout(refSeq)
+
+proc secureRefSlot(i: int): VNodeRef =
+  while refSeq.len <= i:
+    refSeq.add(VNodeRef())
+  result = refSeq[i]
+
+proc view(): VNode =
+  result = buildHtml():
+    tdiv:
+      button(onclick=onClick):
+        text "click me"
+      # storing refs to single elements is straightforward now
+      tdiv(nref=refA):
+        text "A"
+      tdiv(nref=refB):
+        text "B"
+      # It's a bit more tricky when containers are involved:
+      for i, x in modelData.pairs:
+        tdiv(nref=secureRefSlot(i)):
+          text "List item: " & $x
+
+proc renderer(): VNode =
+  view()
+
+setRenderer renderer