atk_nautilus v1.0.2

Nautilus

Nautilus provides a simple syntax for querying objects.

Example

To build a pipeline simply call the search function, give it an object and apply query functions, after the pipeline is constructed it can be evaluated.

let obj = {a: 10, b: {a: [23, 45]}, c: 12};
// it can handle any nested structure of lists and objects
let pipeline = search(obj).all().oftype('number');
// the query is not applied until an evaluation function is called
console.log(pipeline.evaluateWith(Math.max, 0));
// returns 45

API

• Nautilus.search(obj): returns a pipeline with the given object as search space.

Query Functions

All query functions are applied on the search space and return a new pipeline with the resulting search space

• pipeline.key(k): each item in the search space that is an object and has key 'k' is replaced with itemk otherwise the item is removed from the search space.
• pipeline.matchAll(): each item in the search space that is an object is replaced with all child values otherwise the item is removed from the search space.
• pipeline.all(): each item in the search space is recursively opened and all children are added to the search space. (can result in an expensive evaluation)
• pipeline.list(): each item in the search space that is a list is replaced by its values otherwise the item is removed from the search space.
• pipeline.oftype(t): culls search space to only items of type t.
• pipeline.select(f): culls search space to only items where f(t) == true.
• pipeline.where(f): replaces every item in search space by f(item).
• pipeline.custom(f): applies custom query function (see source for examples).

Evaluation Functions

• pipeline.evaluateAll(): gets all items in the search space.
• pipeline.evaluateFirst(): gets the first (or technically last) item in the search space.
• pipeline.evaluateWith(f, s): evaluates search space with reduction function f(res, cur) and start value s.