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3.4 Stack

The most obvious feature of Forth is the stack. When you type in a number, it is pushed on the stack. You can display the contents of the stack with .s.

     1 2 .s
     3 .s

.s displays the top-of-stack to the right, i.e., the numbers appear in .s output as they appeared in the input.

You can print the top element of the stack with ..

     1 2 3 . . .

In general, words consume their stack arguments (.s is an exception).

Assignment: What does the stack contain after 5 6 7 .?