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assumptions

This example provides a simple, limited, implementation of ground linear and intuitionistic assumptions as discussed in the following paper:

@inproceedings{DBLP:conf/slp/TarauDF95,
        author    = {Paul Tarau and Ver{\'o}nica Dahl and Andrew Fall},
        title     = {Backtrackable State with Linear Assumptions, Continuations and Hidden Accumulator Grammars},
        booktitle = {ILPS},
        year      = {1995},
        pages     = {642},
        crossref  = {DBLP:conf/slp/1995},
        bibsource = {DBLP, http://dblp.uni-trier.de}
}

@proceedings{DBLP:conf/slp/1995,
        editor    = {John W. Lloyd},
        title     = {Logic Programming, Proceedings of the 1995 International Symposium, Portland, Oregon, USA, December 4-7, 1995},
        booktitle = {ILPS},
        publisher = {MIT Press},
        year      = {1995},
        isbn      = {0-262-62099-5},
        bibsource = {DBLP, http://dblp.uni-trier.de}
}

A web version of this paper is also available at:

http://www.cse.unt.edu/~tarau/research/PapersHTML/state.html

Print Logtalk, Prolog backend, and kernel versions (if running as a notebook):

%versions

Start by loading the example:

logtalk_load(assumptions(loader)).

Paths example:

%%table
paths::init, paths::path(1, 5, Path).

<!-- Path = [1, 2, 4, 5] ; Path = [1, 3, 5] ; false. -->

Switch example

switch::test(2).

<!-- two true. -->

switch::test(1).

<!-- one true. -->

switch::test(4).

<!-- unexpected(4) true. -->

Grades example:

grades::(assumel(take(hans, german)), grade(hans)).

<!-- true. -->

grades::(assumel(take(hans, italian)), grade(hans)).

<!-- false. -->