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    • Ccg

    Set-termination-method

    Set the default means of proving termination.

    Examples:
    (set-termination-method :ccg)
    (set-termination-method :measure)

    Introduced by the CCG analysis book, this macro sets the default means by which ACL2 will prove termination. Note: This is an event! It does not print the usual event summary but nevertheless changes the ACL2 logical world and is so recorded.

     General Form:
    (set-termination-method tm)

    where tm is :CCG or :MEASURE. The default is :MEASURE (chosen to assure compatibility with books created without CCG). The recommended setting is :CCG. This macro is equivalent to (table acl2-defaults-table :termination-method 'tm), and hence is local to any books and encapsulate events in which it occurs; see ACL2-defaults-table.

    When the termination-method is set to :CCG, a termination proof is attempted using the the hierarchical CCG algorithm CCG-hierarchy.

    When the termination-method is set to :MEASURE, ACL2 attempts to prove termination using its default measure-based method. Thus, in this setting, ACL2's behavior is identical to that when the CCG book is not included at all.

    To see what the current termination method setting is, use get-termination-method.