Basilisk is a value library for Javascript. It allows you to create immutable data in a familiar way, and to derive new versions from that data.

Full documentation is available on readthedocs

var Person = basilisk.makeStruct(['name', 'age']),
    example = new Person({ name: 'Joe', age: 32 }),
    older = example.with_('age', example.age + 2);

Making code which updates deeply nested structures simple and clear is the library's main aim.

// we make a quick alias, to reduce clutter in the code.
var b$ = basilisk.query,

    Person = basilisk.makeStruct(['name', 'age', 'addresses']),
    Address = basilisk.makeStruct(['city', 'country']),

    example = new Person({
        name: 'Joe',
        age: 32, 

        addresses = basilisk.Vector.from([
            new Address({ city: 'London', country: 'United Kingdom' }),
            new Address({ city: 'Cape Town', country: 'South Africa' })
        ])
    }),
    example2, example3;

// first we create a new object, with a US address added.

example2 = b$.swap(example, ['addresses'], function (current) {
    return current.push(new Address({ city: 'Boston', country: 'USA' }));
});

// and if we have to replace a part of that new address.

example3 = b$.replace(example2, ['addresses', b$.at(2), 'city'], 'New York');

What's included

• Structs with new-version helpers.
• Persistent data structures (Vector, HashMap, StringMap) with a Javascript flavor.
• A Query/Update utility to make deep changes in a data store easy to understand.

Examples

There is a simple example application called Listicle.

Documentation

Read all about it on readthedocs.

Installing Basilisk

Note that you need to have an ES5 Shim in place to use Basilisk on older browsers.

• Bower: bower install basilisk
• Node: npm install basilisk

Contributions

Contributions are very welcome! Basilisk is MIT Licensed, so you can use Basilisk in your applications without worry.

Inspired by

Basilisk is heavily inspired by Rich Hickey's talks.

• Value, State Identity - Rich Hickey
• Simple made easy - Rich Hickey