# CPF
A library to work with CPFs.
[![Hex pm](https://img.shields.io/hexpm/v/cpf.svg?style=flat)](https://www.hex.pm/packages/cpf)
[![CircleCI](https://circleci.com/gh/ulissesalmeida/cpf/tree/master.svg?style=svg)](https://circleci.com/gh/ulissesalmeida/cpf/tree/master)
CPF is an acronym for "Cadastro de Pessoa Físicas," it's a unique number
associated with a person that the Brazilian government maintains. With this number,
it is possible to check if a person has any irregularity on tax payments, if they
are alive and many other status that are provided from Brazilian government services
or private company services.
This library provides a validation that checks if the number is a valid CPF
number. The CPF has check digit algorithm is similar to
[`ISBN 10`](https://en.wikipedia.org/wiki/Check_digit#ISBN_10), you can check
the details in Portuguese [here](https://pt.wikipedia.org/wiki/Cadastro_de_pessoas_f%C3%ADsicas#C%C3%A1lculo_do_d%C3%ADgito_verificador).
## Installation
If [available in Hex](https://hex.pm/docs/publish), the package can be installed
by adding `cpf` to your list of dependencies in `mix.exs`:
```elixir
def deps do
[
{:cpf, "~> 0.1.0"}
]
end
```
## Quick Start
You verify if the CPF is valid by calling the function `CPF.valid?/1`:
```elixir
iex> CPF.valid?(563_606_676_73)
true
iex> CPF.valid?(563_606_676_72)
false
```
## Why not other libraries?
This library runs 3 times faster and consume 3 times less memory and work with
primitive types, no extra struct is necessary.
## Docs
The docs can be found at [https://hexdocs.pm/cpf](https://hexdocs.pm/cpf).