ClausesParser

Parses Prolog source into clauses or a Theory.

This layer converts the concrete syntax produced by parser-impl into tuProlog clauses. Each clause gets a fresh variable scope. Recognized op/3 goals update the session operator table only after their containing clause has been parsed, so they affect subsequent clauses but never the directive that declares them. Low-level syntax failures and invalid operator declarations are exposed as it.unibo.tuprolog.core.parsing.ParseException, whose clauseIndex identifies the zero-based failing clause:

val parser = ClausesParser.withStandardOperators()
val theory =
    parser.parseTheory(
        """
        :- op(900, xfy, '::').
        parent(alice, bob).
        ancestor(X, Y) :- parent(X, Y).
        1 :: 2 :: nil.
        """.trimIndent(),
    )

Here :: is only usable as an infix operator starting from the clause that follows the op/3 directive. To parse a single term or clause instead of a whole theory, use it.unibo.tuprolog.core.parsing.TermParser.