Major Section: EVENTS
Examples: (set-measure-function nqthm::count)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-measure-function name)where
name
is a function symbol of one argument. This macro is
equivalent to (table acl2-defaults-table :measure-function 'name)
,
and hence is local
to any books and encapsulate
events
in which it occurs; see acl2-defaults-table. Although this is thus an event
(see table), nevertheless no output results from a set-measure-function
event.
This event sets the default measure function to name
. Subsequently,
if a recursively defined function is submitted to defun
with no
explicitly given :measure
argument, defun
``guesses'' the measure
(name var)
, where name
is the then current default measure function
and var
is the first formal found to be tested along every branch
and changed in every recursive call.
Note that if (table acl2-defaults-table :measure-function 'name)
has its
default value of nil
, then the default measure function is
acl2-count
.