Create AboutStackNotation.md

notes/forth/AboutStackNotation.md

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+#  ABOUT STACK NOTATION
+
+  __The top of the stack is to the right.__, 
+        Forth 2012, Standart.
+
+  __ OVER  ( n1 n2 — n1 n2 n1 )  Copies second item to top__, 
+        "Starting Forth", Leo Brodie
+
+  I have a cognitive problem about stack notation.
+
+  It represents the order of "pushed into the stack", 
+  not the order "count from top of stack".
+
+  In standards 79, 83, 94, the cells in ( after -- before ), 
+  should be arranged on the left as bottom and on the right as top.
+
+  For example, when representing ( w1 w2 w3 -- ), the order 
+  is be w3 at the top and w1 at the bottom.
+
+  The cells indices for 
+
+        ( w1 w2 w3 -- ), are of w1 is 3 and of w2 is 2,
+
+  but for 
+
+        ( w1 w2    -- ), are of w1 is 2 and of w2 is 1.
+
+  This is very confusing to me, when using the stack in words.
+
+  I prefer to use w1 always at top, and the following indicating 
+  the position relative to the top of the stack, as the depth level.
+
+  So w1 will always be 1, w2 will always be 2, and so on,
+  the indices are always in the same order.
+
+  To differentiate, I'm using double parentheses as comments of stack 
+  elements to indicate the top of stack is at left, thus, 
+  it is ever the last element pushed into stack.