lib-jsl/test/samples/ir/query-exercise-4.59-c.js

JSL is a JSON based logic programming library meant for embedded use

/*
c. Alyssa arrives at work on Wednesday morning and wonders what meetings she has to attend that day. 
Having defined the above rule, what query should she make to find this out?


*/

var JSL = require('../../..');

var ruleset = require ('./db.js');

var meetings = [
    [{meeting : { department : 'accounting', day : 'Monday', hour : 9, minute : 0} }],
    [{meeting : { department : 'administration', day : 'Monday', hour : 10, minute : 0} }],
    [{meeting : { department : 'computer', day : 'Wednesday', hour : 15, minute : 0} }],
    [{meeting : { department : 'administration', day : 'Friday', hour : 13, minute : 0} }],
    [{meeting : { department : 'whole-company', day : 'Wednesday', hour : 13, minute : 0} }],
];

var filterRules = [
    [
        { meeting_time : { person : '$person', dept : '$dept', day : '$day', hour : '$hour', minute : '$minute' } },
        { job : { name : '$person', title : '$title'} },
        { meeting : { department : '$dept', day : '$day', hour : '$hour', minute : '$minute' } },
        { $or : [
            { $call : [ 'deptMatch', '$title', '$dept'] },
            {$bind : [ '$dept', 'whole-company'] }
        ]}
    ]
];

function deptMatch (title, dept) {
    var re = new RegExp('^' + dept + '\\s+');
    return title.match(re); // match returns null on failure, which is what we need callbacks to return on failure
}

var callbacks = { 
    deptMatch : deptMatch
};
// sample query to get Alyssa P Hacker's meetings for the whole week

var query = [ { meeting_time : { person : 'Hacker Alyssa P', dept : '$dept', day : 'Wednesday', hour : '$hour', minute : '$min'} } ]; 
var transform = { person : 'Hacker Alyssa P', dept : '$dept', day : 'Wednesday', hour : '$hour', minute : '$min'};

var jsl = new JSL({rules : ruleset.concat(meetings, filterRules), query: query, transform: transform, callbacks : callbacks});
var response = jsl.run();

module.exports = response;