Prolog - functional term vs predicate

prolog

Solution

If I can remember correctly:

A functional term is a type of term that looks like pred_name(...). The parser deals with terms, which also include constants and variables.

A predicate is not the name of the thing, but the thing itself; something which is either true or false. Functional terms are used to define and call predicates.

So, strictly speaking, terms don't succeed or fail, and you can't parse predicates. It is much like the difference between a numeral and a number.

Problem

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