# ex_fpe v0.1.0 - Table of Contents

> Format-preserving encryption (FF1 and FF3-1).

## Pages

- [ExFPE](readme.md)
- [Changelog](changelog.md)
- [LICENSE](license.md)

## Modules

- [ExFPE](ExFPE.md): Format-preserving encryption (FPE) for Elixir.
- [ExFPE.Codec.Builtin](ExFPE.Codec.Builtin.md): Handles alphabets made up of digits 0 to 9 and letters a to z, in that order,
with all letters of equal casing, encompassing radixes from 2 and up to 36.
- [ExFPE.Codec.Custom](ExFPE.Codec.Custom.md): Handles custom alphabets — those other than the ones supported by
`ExFPE.Codec.Builtin`.
- [ExFPE.FF1](ExFPE.FF1.md): The FF1 format-preserving encryption mode.
- [ExFPE.FF3_1](ExFPE.FF3_1.md): The FF3-1 format-preserving encryption mode.
- [ExFPE.FFX](ExFPE.FFX.md): FFX definitions.

- Exceptions
  - [ExFPE.ArgumentError](ExFPE.ArgumentError.md): Raised by `ExFPE.new!/3` when a context cannot be built — an invalid key, mode,
radix, or alphabet.
  - [ExFPE.InputError](ExFPE.InputError.md): Raised by `ExFPE.encrypt!/3` and `ExFPE.decrypt!/3` when the tweak or the input
numerical string is invalid.
  - [ExFPE.NotStartedError](ExFPE.NotStartedError.md): Raised by a `use ExFPE` module's generated functions when its context is not
running — usually because it is missing from the supervision tree, or the
application is stopped.

