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Control Structure

(:or  path tex2html_wrap_inline1490 ...path tex2html_wrap_inline1492 )

:or queries its paths in order, returning the stream of bindings produced by the first one that succeeds. The following paths are not queried at all.

(:all-paths  path1 path2)

:all-paths first queries path1. If it appears within a query, it then queries path2 under every substitution generated by the first query and succeeds iff all of these queries succeed. If it appears within an assertion it asserts path2 under every substitution generated by the first query and succeeds iff all of these assertions succeed. For example, one could query ``Are all Adam's children male?'' as:

displaymath1524

Note that, like :unp, :all-paths and :or are non-monotonic.



Micheal S. Hewett
Tue Oct 29 11:28:38 CST 1996