A library to work with CPFs.

[![Hex pm](](
[![Coverage Status](](

CPF is an acronym for "Cadastro de Pessoa Físicas," it's a unique number
associated to a person that the Brazilian government maintains. With this
number, it is possible to check or retrieve information about a person.

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`](, you can check
the details in Portuguese [here](

## Installation

If [available in Hex](, the package can be installed
by adding `cpf` to your list of dependencies in `mix.exs`:

def deps do
    {:cpf, "~> 0.8"}

## Quick Start

You can verify if a CPF is valid by calling the function `CPF.valid?/1`:

iex> CPF.valid?(563_606_676_73)

iex> CPF.valid?(563_606_676_72)

iex> CPF.valid?("563.606.676-73")

iex> CPF.valid?("563.606.676-72")

iex> CPF.valid?("56360667673")

iex> CPF.valid?("56360667672")

## Parsing and Storing CPFs

If you want to store CPF as integer or as `String.t`, this library have
you covered. You can do:

iex> "044.858.476-08" |> CPF.parse!() |> CPF.to_integer()

iex> "044.858.476-08" |> CPF.parse!() |> to_string()

Storing CPF as strings are easier for a human to read since the 0 padding digits
are there. Meanwhile, storing as integers will allow you have better performance
in CPF lookups.

The `CPF.parse/1` and `CPF.parse!/1` returns you the CPF value wrapped in a
custom type with explicit digits.

iex> CPF.parse("044.858.476-08")
{:ok, #CPF<"044.858.476-08">}

iex> CPF.parse("044.858.476-07")
{:error, %CPF.ParsingError{reason: :invalid_verifier}}

iex> CPF.parse!("044.858.476-08")

iex> CPF.parse!("044.858.476-07")
** (CPF.ParsingError) invalid verifier

With the casted CPF in hands, you can use `CPF.format/1`, `CPF.to_integer/1` and

## CPF Formatting

If you have a valid CPF strings or integer in hands, you can use `` and
in sequence call `CPF.format/1`:

iex> 4485847608 |> |> CPF.format()

iex> "04485847608" |> |> CPF.format()

The `CPF.format/1` expects the input be wrapped in the CPF type. Remember, only
use `` with valid CPFs, no other checks are done there. If you need some
validation, use `CPF.parse/1`.

## Generating random CPFs for testing

You can generate valid CPF numbers by using `CPF.generate/0`:

iex> CPF.generate()

iex> CPF.generate() |> to_string()

iex> CPF.generate() |> CPF.to_integer()

iex> CPF.generateI() |> CPF.format()

After you generate the CPF, you can turn the CPF into a formatted string, or
convert to a string digits, or convert to integer.

## Flexibilizing the CPF validation

You can use `CPF.flex/1` when you only care if the user has provided the
correct number before any validation or parsing. For example:

iex> "04.4.8*58().476-08" |> CPF.flex() |> CPF.valid?()

iex> "04.4.8*58().476-08" |> CPF.flex() |> CPF.parse!() |> CPF.format()

It can be useful to take a user's dirty input and format it.

## Command line

You can generate random valid CPFs with:

$ mix cpf.gen

$ mix cpf.gen --format=digits --count=2

You can also check if CPF are valid with:

$ mix cpf.check 194.925.115-25

Run `mix help cpf.gen` and `mix help cpf.check` to read a further explanation
about the commands available options.

## 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 [](