query.ts

Purpose

Integration of Nrgy.js with Query objects from the rx-effects library.

Overview

This file provides mechanisms for mutual conversion between Atom from Nrgy and Query from rx-effects. This allows atoms to be used where Query objects are expected, and vice versa.

Conceptual Architecture

Query is an object with a get() method and a value$ property (Observable).

• toQuery: wraps an Atom, using its call for get() and observe(source) for value$.
• fromQuery: subscribes to value$ and stores the state in an internal atom. The resulting atom is a computed atom (compute), which returns a value or throws an error depending on the subscription state.

Public API Description

toQuery<T>(source: Atom<T>): Query<T>

Converts an Nrgy Atom into a Query.

• source: The source Nrgy Atom.

fromQuery<T>(query: Query<T>): DestroyableAtom<T>

Converts a Query into an Nrgy Atom.

• query: The source Query object.

Usage Examples

import { atom } from '@nrgyjs/core';
import { toQuery, fromQuery } from '@nrgyjs/rx-effects';

const count = atom(10);
const countQuery = toQuery(count);

console.log(countQuery.get()); // 10
countQuery.value$.subscribe(v => console.log(v));