https://github.com/lpil/formal

https://github.com/lpil/formal

Last synced: about 1 month ago
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• Host: GitHub
• URL: https://github.com/lpil/formal
• Owner: lpil
• Created: 2024-02-27T22:13:27.000Z (9 months ago)
• Default Branch: main
• Last Pushed: 2024-02-29T10:46:36.000Z (9 months ago)
• Last Synced: 2024-05-01T23:04:56.702Z (6 months ago)
• Language: Gleam
• Size: 9.77 KB
• Stars: 10
• Watchers: 2
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md

Awesome Lists containing this project

• awesome-gleam - formal - [📚](https://hexdocs.pm/formal/) - Type safe HTML form decoding and validation! (Packages / HTML)

README

        
# formal

Type safe HTML form decoding and validation!

[![Package Version](https://img.shields.io/hexpm/v/formal)](https://hex.pm/packages/formal)

[![Hex Docs](https://img.shields.io/badge/hex-docs-ffaff3)](https://hexdocs.pm/formal/)

```sh

gleam add formal

```

```gleam

import formal/form

// Define a type that is to be decoded from the form data

pub type SignUp {

  SignUp(email: String, password: String)

}

// This function takes the list of key-value string pairs that a HTML form

// produces. It then decodes the form data into a SignUp value, ensuring that

// all the fields are present and valid.

//

pub fn handle_form_submission(values: List(#(String, String))) {

  let result = 

    form.decoding({

      use email <- form.parameter

      use password <- form.parameter

      SignUp(email: email, password: password)

    })

    |> form.with_values(values)

    |> form.field(

      "email",

      form.string

        |> form.and(form.must_not_be_empty)

        |> form.and(form.must_be_an_email),

    )

    |> form.field(

      "password",

      form.string

        |> form.and(form.must_not_be_empty)

        |> form.and(form.must_be_string_longer_than(7))

    )

    |> form.finish

  case result {

    Ok(data) -> {

      // Do something with the SignUp value here

    }

    Error(form_state) -> {

      // Re-render the form with the error messages

    }

  }

}

```

An example of using this library with Wisp and Lustre can be found in

[./example/](https://github.com/lpil/formal/tree/main/example).

Further documentation can be found at .