We propose HHWeb, an extension to LogicWeb with hereditary Harrop formulas. HHWeb extends the LogicWeb of Loke and Davison by allowing goals of the form (existence x_1 ... existence x_nD) contains G (or equivalently any x_1 ... any x_n(D contains G)) where D is a web page and G is a goal. This goal is intended to be solved by instantiating x_1,...,x_n in D by new names and then solving the resulting goal. The existential quantifications at the head of web pages are particularly flexible in controlling the visibility of names. For example, they can provide scope to functions and constants as well as to predicates. In addition, they have such simple semantics that implementation becomes more efficient. Finally, they provide a client-side interface which is useful for customizing web pages.
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