nature

library under construction

Nature

The Nature library provides a class (Thing) which creates objects with strict, per-property type and value checking. This enables more fine-grained classification base on type and state. Say you have a Person class, with nature you can create a sub-class of Person in a particular state, e.g. Drunkard, Scoundrel, Leader etc. These Things can be reused, subclassed or merged with other Things to create new hybrids. The Thing class adds these features to each new object:

• Type and value validation per property
• Data loading from the command line, environment, external file or plain object
• Merging and cloning
• Property grouping and filtering
• A general mechanism for duck typing

Synopsis

Enables you to write an API method like: (Scoundrel and FlammableCar are derivitives of Thing)

exports.burnCar = function(arsonist){
    var scoundrel = new Scoundrel(arsonist);
    if (!scoundrel.valid){
        throw new Error(scoundrel.validationMessages.join("\n"));
        // throws:
        // The arsonist supplied must be a Scoundrel, you passed a Metrosexual
        // Invalid age 29: Must be between 11 and 19. 
        // Over 5 litres Gasoline required
        // Less compassion necessary.
    } else {
        var car = new FlammableCar(process.env);
        if (car.valid){
            // the Vauxhall Astra supplied in the environment is indeed flammable
            scoundrel.igniteCar(car);
        }
    }
}

Client code for the above is straight forward. In this case burnCar() input is taken directly from the command line. You can also pass the environment (process.env), an object literal or a Thing instance.

var outdoors = require("outdoor-activity");
outdoors.burnCar(process.argv);

Then a simple command executes the outdoor activity:

$ CAR_MAKE=Vauxhall CAR_MODEL=Astra node outdoors.js --name Alfie --age 11 --litres 13 --compassion unknown

See the Thing docs for more detail..