option_experiment.js

exports.OptionMonad = {
    bind: function(f, m) {
              if (m.isEmpty) return m;
              else return f(m.value);
              },
    unit: function(x) { return new exports.Option(x); },
}

exports.Option = (function() {
    return function(x) {
        var is_empty = typeof x == 'undefined' || x == null
        return { value: x, isEmpty: is_empty, toString: function() {
            if (is_empty) return "{Empty}";
            else return "{Just " + x + "}";
        } };
    };
})();