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NDL scripts
A script is a sequence of phrases (signature declarations
and/or assertions and/or deductions), possibly separated
by periods. The following is a sample script:
Constants Mary, Tom.
Functions f:1, g:2.
Relations P:1, Q:1, loves:2.
assert (forall x (Tom loves x)).
assume Mary loves Tom
begin
specialize (forall x (Tom loves x)) with Mary;
both Tom loves Mary, Mary loves Tom
end
Here Constants Tom, Mary introduces Tom and Mary
as constant symbols. The phrase Functions f:1, g:2
declares f and g to be function symbols of arity
1 and 2, respectively. Similarly, the declaration Relations P:1, Q:1,
R:2 declares P and Q to be unary relation symbols (of
arity 1) and loves to be a binary relation symbol (of arity 2).
The keyword assume marks the beginning of a deduction; we will
cover deductions in Section 1.9.
2004-08-06