`FunctionalCuid` is a CUID generator written in and designed for F#, which can be used from any .NET language.
## What Is a CUID?
The best answer to that question can be found on [the README from the author](https://github.com/ericelliott/cuid). The short version is that it's a Collision-resistant Unique IDentifier (CUID) that can be generated wherever it needs to be (similar to GUIDs), but also follows a format that make them ever-increasing, which means that they can be indexed by even the most rudimentary of database systems.
## Installing
(nuget link here)
## Usage
For F#, `FunctionalCuid` provides `Cuid` and `Slug` types as single-case discriminated unions, and modules to generate these types and convert them to their string representations. For string-based purposes, both `Cuid` and `Slug` also have a `generateString` function that returns the same value, just as a string.
In F#...
```fsharp
module Examples
open Cuid
/// A CUID generated as the CUID type
let generatedCuid = Cuid.generate ()
/// Creating a CUID from a string you already know. This string must be 25
/// characters long and start with "c".
let cuidFromString =
match Cuid.fromString "cjz362bgd00005cus6t21gba0" with
| Error msg -> invalidOp msg
| Ok cuid -> cuid
/// The string representation of a CUID
let cuidString = Cuid.generateString ()
```
For the `Slug` type, just replace `Cuid` with `Slug`; the validation rules for `Slug.fromString` are simply that the string has to be between 7 and 10 characters long.
For C# and VB.NET, the syntax is a bit different. Instead of `Cuid` as it reads above, it will appear as `CuidModule`; and, as `generateString` is the most likely function (method) called from those languages, its compiled name uses Pascal case. The same holds true for the `Slug` modules as well. A C# example...