Original Post
i am stuck on a simple problem in my prolog
program.
in the prolog prompt type:
3 > 4.
... it produces NO
4 > 3.
... it produces YES
4 = 3.
... NO
4 = 4.
... YES
watch here:
X = X.
... X = H3
... YES
X = 3.
... X = 3
... YES
my trouble is here:
X > 3.
... ERROR while executing >/2
what i want is to make somehow a logical test,
that tells me if X is larger than a specified value,
but when X is not unified to a specific value,
the test fails(NO), not producing error.
what i want to do is somthing like:
----------
is_this_larger_than_three(Value):-
Value > 3.
----------
so that:
is_this_larger_than_three(5).
... YES
is_this_larger_than_three(2).
... NO
is_this_larger_than_three(_).
... NO [not an error, as it does to me]
guess there must be a way to know that
Value , is unified or not,
and if its not unified it fails.
smthn like:
-----------
is_this_larger_than_three(Value):-
is_this_unified(Value), %how to do this?!?!
Value > 3.
-----------
[edited by - zaidgs on May 5, 2004 6:47:58 AM]
