swift-dependencies

# Dependencies

A dependency management library inspired by SwiftUI's "environment."

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  * [Learn More](#learn-more)
  * [Overview](#overview)
  * [Quick start](#quick-start)
  * [Examples](#examples)
  * [Documentation](#documentation)
  * [Installation](#installation)
  * [Community](#community)
  * [Extensions](#extensions)
  * [Alternatives](#alternatives)
  * [License](#license)

## Learn More

This library was motivated and designed over the course of many episodes on
[Point-Free](https://www.pointfree.co), a video series exploring functional programming and the
Swift language, hosted by [Brandon Williams](https://twitter.com/mbrandonw) and [Stephen
Celis](https://twitter.com/stephencelis).

<a href="https://www.pointfree.co">
  <img alt="video poster image" src="https://d3rccdn33rt8ze.cloudfront.net/episodes/0209.jpeg" width="600">
</a>

## Overview

Dependencies are the types and functions in your application that need to interact with outside
systems that you do not control. Classic examples of this are API clients that make network
requests to servers, but also seemingly innocuous things such as `UUID` and `Date` initializers,
file access, user defaults, and even clocks and timers, can all be thought of as dependencies.

You can get really far in application development without ever thinking about dependency management 
(or, as some like to call it, "dependency injection"), but eventually uncontrolled dependencies can 
cause many problems in your code base and development cycle:

  * Uncontrolled dependencies make it **difficult to write fast, deterministic tests** because you 
    are susceptible to the vagaries of the outside world, such as file systems, network 
    connectivity, internet speed, server uptime, and more.
    
  * Many dependencies **do not work well in SwiftUI previews**, such as location managers and speech
    recognizers, and some **do not work even in simulators**, such as motion managers, and more. 
    This prevents you from being able to easily iterate on the design of features if you make use of 
    those fra