# Return a new variable read that contains the value of the expression
	# This method take care efficiently of creating and initalising an anonymous local variable
	#
	# Note: since this method do side-effects (AST replacement), there could be unexpected effects when used as
	# argument of other methods related to AST transformations.
	fun make_var_read: AVarExpr
	do
		var variable = self.variable_cache
		if variable == null then
			assert parent != null
			var place = detach_with_placeholder
			variable = new Variable("")
			variable.declared_type = self.mtype
			var nvar = new AVarAssignExpr.make(variable, self)
			place.replace_with(nvar)
			self.variable_cache = variable
		end
		return new AVarExpr.make(variable, variable.declared_type.as(not null))
	end