JESS: Test conditional element

[Ben Allen]

From reading the paragraph below from the Jess language spec.

"A pattern with test as the head is special; the body consists not of a 
pattern to match against the
knowledge base but of one or more boolean functions, which are evaluated in 
order. The results
determine whether the pattern matches. A test pattern fails if and only if 
one of the functions evaluates
to the atom FALSE; if they all evaluate to TRUE or any other value, the 
pattern with "match." "

I had taken this to mean that the test conditional element could be 
followed by a number of functions that return boolean results. For example, 
i would expect to be able to use the following rule:

(defrule testing-test
        "Test to see if the test conditional element can take more than one function"
        ;LHS
        (test (< 3 2) (< 3 2))
        =>
        ;RHS
        (printout t "testing-test satisfied" crlf)
)
However, this generates the following error:

Jess> (batch ben_ex/testTest.clp)
Jess reported an error in routine Jesp.parsePattern
        while executing (batch ben_ex/testTest.clp).
  Message: Expected ')' .
  Program text: ( defrule testing-test "Test to see if the test 
conditional elem
ent can take more than one function" ( test ( < 3 2 ) (  at line 5.
        at jess.Jesp.parseError(Jesp.java:1622)
        at jess.Jesp.parsePattern(Jesp.java:1229)
        at jess.Jesp.parseLHS(Jesp.java:1111)
        at jess.Jesp.doParseDefrule(Jesp.java:933)
        at jess.Jesp.parseDefrule(Jesp.java:893)
        at jess.Jesp.parseSexp(Jesp.java:149)
        at jess.Jesp.parse(Jesp.java:69)
        at jess.Jesp.parse(Jesp.java:54)
        at jess.Batch.batch(Batch.java:43)
        at jess.Batch.call(Batch.java:57)
        at jess.FunctionHolder.call(FunctionHolder.java:30)
        at jess.Funcall.execute(Funcall.java:266)
        at jess.Jesp.parseAndExecuteFuncall(Jesp.java:1590)
        at jess.Jesp.parseSexp(Jesp.java:173)
        at jess.Jesp.parse(Jesp.java:69)
        at jess.Jesp.parse(Jesp.java:54)
        at jess.Main.execute(Main.java:126)
        at jess.Main.main(Main.java:24)

This error would suggest that only one function can be passed to the test 
CE. This would in turn suggest that if i wished to implement the above 
example, i would have to write the example in the style below:

(defrule testing-test
        "Test to see if the test conditional element can take more than one function"
        ;LHS
        (test (< 3 2))
        (test (< 3 2))
        =>
        ;RHS
        (printout t "testing-test satisfied" crlf)
)
Which does parse.

I am slightly confused. Have i made an oversight or is this just the way 
you have to work work with the test CE i.e. multiple test elements as 
opposed to a single test element containing multiple functions?

Any help would be greatly appreciated,

Ben Allen

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