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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