Stack

Displays the current contents of the stack. Can be used to view stack contents during stepwise execution. Nevertheless the proof tree is more convenient.

Each row of the Stack window corresponds to some element of the tail of a rule. The Stack window contain three columns of numbers:

Column #0 counts the stack boxes.

Column #1 contains the number of father box.

Column #2 contains the number of the element inside the tail of its rule, and totality of the elements in the tail of this rule.

Column #3 contains the number of the clause that has been already unified with this element, and, next to this number, the numbers of the other clauses, that can be unified with this element, in case of backtracking.