Initial revision
diff --git a/Lib/lib-stdwin/Split.py b/Lib/lib-stdwin/Split.py
new file mode 100644
index 0000000..c442fe3
--- /dev/null
+++ b/Lib/lib-stdwin/Split.py
@@ -0,0 +1,113 @@
+# Generic Split implementation.
+# Use as a base class for other splits.
+
+Error = 'Split.Error'	# Exception
+
+import rect
+from util import remove
+
+class Split():
+	#
+	# Calls from creator
+	# NB derived classes may add parameters to create()
+	#
+	def create(self, parent):
+		parent.addchild(self)
+		self.parent = parent
+		self.children = []
+		self.mouse_interest = []
+		self.timer_interest = []
+		self.mouse_focus = 0
+		return self
+	#
+	# Downcalls from parent to child
+	#
+	def destroy(self):
+		self.parent = 0
+		for child in self.children:
+			child.destroy()
+		self.children[:] = []
+		self.mouse_interest[:] = []
+		self.timer_interest[:] = []
+		self.mouse_focus = 0
+	#
+	def minsize(self, m): return unimpl()
+	def getbounds(self): return unimpl()
+	def setbounds(self, bounds): unimpl()
+	def draw(self, args):
+		# (Could avoid calls to children outside the area)
+		for child in self.children:
+			child.draw(args)
+	#
+	# Downcalls only made after certain upcalls
+	#
+	def mouse_down(self, detail):
+		if self.mouse_focus:
+			self.mouse_focus.mouse_down(detail)
+		p = detail[0]
+		for child in self.mouse_interest:
+			if rect.pointinrect(p, child.getbounds()):
+				self.mouse_focus = child
+				child.mouse_down(detail)
+	def mouse_move(self, detail):
+		if self.mouse_focus:
+			self.mouse_focus.mouse_move(detail)
+	def mouse_up(self, detail):
+		if self.mouse_focus:
+			self.mouse_focus.mouse_up(detail)
+			self.mouse_focus = 0
+	#
+	def timer(self):
+		for child in self.timer_interest:
+			child.timer()
+	#
+	# Upcalls from child to parent
+	#
+	def addchild(self, child):
+		if child in self.children:
+			raise Error, 'addchild: child already inlist'
+		self.children.append(child)
+	def delchild(self, child):
+		if child not in self.children:
+			raise Error, 'delchild: child not in list'
+		remove(child, self.children)
+		if child in self.mouse_interest:
+			remove(child, self.mouse_interest)
+		if child in self.timer_interest:
+			remove(child, self.timer_interest)
+		if child = self.mouse_focus:
+			self.mouse_focus = 0
+	#
+	def need_mouse(self, child):
+		if child not in self.mouse_interest:
+			self.mouse_interest.append(child)
+			self.parent.need_mouse(self)
+	def no_mouse(self, child):
+		if child in self.mouse_interest:
+			remove(child, self.mouse_interest)
+			if not self.mouse_interest:
+				self.parent.no_mouse(self)
+	#
+	def need_timer(self, child):
+		if child not in self.timer_interest:
+			self.timer_interest.append(child)
+			self.parent.need_timer(self)
+	def no_timer(self, child):
+		if child in self.timer_interest:
+			remove(child, self.timer_interest)
+			if not self.timer_interest:
+				self.parent.no_timer(self)
+	#
+	# The rest are transparent:
+	#
+	def begindrawing(self):
+		return self.parent.begindrawing()
+	def beginmeasuring(self):
+		return self.parent.beginmeasuring()
+	#
+	def change(self, area):
+		self.parent.change(area)
+	def scroll(self, args):
+		self.parent.scroll(args)
+	def settimer(self, itimer):
+		self.parent.settimer(itimer)