Here are some examples of arithmetic expressions that use
infix operators:

All the infix operators used in the
above are necessarily * binary* operators ---* i.e.* they
have an arity of 2. Each of the above terms can be rewritten in `regular' ** Prolog** syntax
as

Remember that the use of the inequality operators requires
that both arguments are evaluated before unification is applied.
For ** is/2**, only the second argument is evaluated before unification is applied.

Here are some examples of infix operators used in the basic
syntax of ** Prolog** clauses.

These infix operators are also binary. Here are their regular forms.

Note how the functor ** ,/2** has to be `protected'
with single quotes as in ** ','**.

Mon May 24 20:14:48 BST 1999