A technique for generating almost optimal Floyd-Evans productions for precedence grammars

A technique is developed for generating almost optimal Floyd-Evans productions given a precedence grammar. A graph formulation is used for the problem of merging productions. The productions generated correspond to the minimum cost inverse-arborescence of that graph. The validity of the technique is demonstrated for weak precedence grammars defined here, but the productions mechanically generated for any precedence grammar can often be modified in such a way that correct, almost optimal parsers are obtained.