higher-ordered-currying

// here's an example of both higher order functions and currying.
// jquery's 'on' and 'each' are both higher order functions, as we pass functions as arguments.
// before we use the saveSubscriber function within the anonymous function passed into each, we curry it with the total # rows
// to establish an upper limit (so we know when we've processed the last row) - the returned function is saveRow

$(document).on('click', '#save-permissions', function() {
    var $modifiedRows = $('#subscribers-bulk').find('tr.modified');
    // here we curry saveSubscriber, passing in the the number of modified rows
    var saveRow = saveSubscriber($modifiedRows.length);
    $modifiedRows.each(function(index) {
        saveRow(this, index);
    });
});

function saveSubscribers(count) {
    var errors = 0;

    return function(row, index) {
        var $row = null;
        if (row instanceof $) $row = row;
        else $row = $(row);

        var $submitIcon = $('#manage-subscribers-content').find('#save-permissions > i');

        var options = {
            data: {
                // some data to pass to the srver
            },
            success: function (res) {
                var hasError = !res || res.error;
                errors += hasError ? 1 : 0;
                $row.removeClass('modified').toggleClass('danger', hasError).toggleClass('success', !hasError);

                if (count - 1 === index) {
                    $submitIcon.removeClass('fa-pulse fa-spinner').addClass('fa-save');
                    if (errors > 0)
                        sweetAlert('Uh oh!', 'An error occurred updating a subscriber. The subscribers highlighted in red had errors.', 'error');
                    else
                        sweetAlert('Success!', 'All subscribers updated successfully.', 'success');
                }
            }
        };

        $submitIcon.removeClass('fa-save').addClass('fa-pulse fa-spinner');
        helpers.call('/pro/savesubscriber', options);
    }
}