lib/instructions/exec/exec_yankdup.rb in nudge-0.2.6 vs lib/instructions/exec/exec_yankdup.rb in nudge-0.2.7

@@ -1,4 +1,16 @@
+# pops the top item of the +:int+ stack (the "index");
+# pushes a duplicate of an item from down "inside" the +:exec+ stack to its top.
+# 
+# If the index value is negative or 0, the bottom item on the stack is copied;
+# if the index value is greater than or equal to the depth of the stack, the top item is copied;
+# otherwise, the index value refers to the bottom-to-top order of stack items.
+#
+# *needs:* 1 +:int+, 1 +:exec+
+#
+# *pushes:* 1 +:exec+ (sortof)
+#
+
 class ExecYankdupInstruction < Instruction
   include YankdupInstruction
   def initialize(context)
     super(context, :exec)
   end