[![ Version](](
[![Build Status](](

[Classless Inter-Domain Routing](
(CIDR) utilities for [Elixir](

## Setup

To use this library in your project, edit your `mix.exs` file and add `:cidr`
as a dependency:

defp deps do
    {:cidr, ">= 0.3.0"}

## Usage

When you pass in an IP address string into `CIDR.parse`, you get a `%CIDR{}`
struct back. This contains the start and end addresses as Erlang IP tuples,
the amount of hosts the range covers and the mask.

iex(1)> cidr = "" |> CIDR.parse
%CIDR{start: {1, 2, 3, 0}, end: {1, 2, 3, 255}, hosts: 256, mask: 24}

You can query the struct for all of its fields:

iex(2)> cidr.start
{1, 2, 3, 0}
iex(3)> cidr.hosts

And use it to see if other IP addresses fall in the same range:

iex(4)> cidr |> CIDR.match!({1,2,3,100})
iex(5)> cidr |> CIDR.match!({1,2,4,1})

The match function also supports IP strings:

iex(6)> cidr |> CIDR.match!("")
iex(7)> cidr |> CIDR.match!("")

Keep in mind that `match!/2` throws an ArgumentError when you pass in a value
that does not represent a valid IP address or when you try to match an IPv4
address with an IPv6 range and vice-versa. We also provide `match/2`, a non-
throwing interface that returns tagged tuples.

## Contribution Process

This project uses the [C4.1 process]( for all
code changes.

> "Everyone, without distinction or discrimination, SHALL have an equal right
> to become a Contributor under the terms of this contract."

### TL;DR

1. Check for [open issues]( or
[open a new issue]( to start
a discussion around a feature idea or a bug.
2. Fork the [cidr-elixir repository on Github](
to start making your changes.
3. Write a test which shows that the bug was fixed or that the feature works as
4. Send a pull request and wait for it to be merged

## License

[MIT License](LICENSE).