functional-moment

Demothodizing Moment.js to use the library in a more functional style.

Functional moment is an experimental library created by using Ramda (another experimental library) to create semi equivalent functions of the methods on Moment and Duration objects.

Examples

var test = require('tape');
var moment = require('moment');
var R = require('ramda');
var fm = require('functional-moment');

var entries = [
    {
        date: '2014-01-23',
        duration: 30 * 60
    },
    {
        date: '2014-01-23',
        duration: 1 * 60
    },
    {
        date: 'Not a valid date',
        duration: 4 * 60 * 60
    }
];



test('moment test', function (t) {
    var dates = R.map(R.compose(moment, R.prop('date')), entries);
    var validDates = R.filter(fm.isValid, dates);

    // All the functional-moment functions are currently curried functions
    var dateFormatter = fm.format('MM/DD/YYYY');
    var formattedDates = R.map(dateFormatter, validDates);

    t.plan(5);
    t.equal(validDates.length, 2);
    t.equal(typeof dateFormatter, 'function');
    t.equal(dateFormatter(moment('2014-01-10')), '01/10/2014');
    t.equal(formattedDates.length, 2);
    t.equal(formattedDates[0], '01/23/2014');
});

test('duration test', function (t) {
    var duration = R.rPartial(moment.duration, 'seconds');
    var durations = R.map(R.compose(duration, R.prop('duration')), entries);

    // All the functional-moment functions are currently curried functions
    var humanizer = fm.duration.humanize(false);
    var humanDurations = R.map(humanizer, durations);

    t.plan(5);
    t.equal(typeof humanizer, 'function');
    t.equal(humanizer.length, 1);
    t.equal(humanDurations[0], '30 minutes');
    t.equal(humanDurations[1], 'a minute');
    t.equal(humanDurations[2], '4 hours');

});

Problems

This is currently a really basic attempt at demothodizing the awesome Moment.js library. A few of the problems are:

• It does not respect any default values. If the method can take an option input (for instance Moment#format takes an optional format). These values are now required as a parameter
• Functions that can act as a getter/setter can currently only set (because parameters are required)
• It feels weird to have the functions require a Moment/Duration as the input. I think if the input is something that could create a valid Moment or Duration it should do so