https://github.com/lue-bird/elm-syntax-to-gleam

transpile elm to gleam
https://github.com/lue-bird/elm-syntax-to-gleam

elm elm-syntax gleam transpiler

Last synced: 6 days ago
JSON representation

transpile elm to gleam

• Host: GitHub
• URL: https://github.com/lue-bird/elm-syntax-to-gleam
• Owner: lue-bird
• License: mit
• Created: 2025-01-15T23:57:50.000Z (8 days ago)
• Default Branch: main
• Last Pushed: 2025-01-16T14:34:22.000Z (8 days ago)
• Last Synced: 2025-01-16T15:29:47.380Z (8 days ago)
• Topics: elm, elm-syntax, gleam, transpiler
• Language: Elm
• Homepage:
• Size: 47.9 KB
• Stars: 0
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Changelog: changes.md
  • License: LICENSE

Awesome Lists containing this project

README

        
> Status: gleam seems to hate record access as much as any other languages not called elm.

Investigating why editor tooling again knows the type better than the compiler.

Print pure [`elm-syntax`](https://dark.elm.dmy.fr/packages/stil4m/elm-syntax/latest/) declarations as

[gleam](https://gleam.run/) code.

```elm

import Elm.Parser

import ElmSyntaxToGleam

"""module Sample exposing (..)

plus2 : Int -> Int

plus2 n =

    n + ([ 2 ] |> List.sum)

"""

    |> Elm.Parser.parseToFile

    |> Result.mapError (\_ -> "failed to parse elm source code")

    |> Result.map

        (\syntaxModule ->

            [ syntaxModule ]

                |> ElmSyntaxToGleam.modules

                |> .declarations

                |> ElmSyntaxToGleam.gleamDeclarationsToModuleString

        )

-->

Ok """..some default declarations and imports..

pub fn sample_plus2() -> fn(Float) -> Float {

    fn(n) { float.add(n, float.sum([ 2.0 ])) }

}

"""

```

To try it out, you can

run [this node script](https://github.com/lue-bird/elm-syntax-to-gleam/tree/main/node-elm-to-gleam).

### be aware

-   only a subset of elm is currently supported. not supported:

    -   `elm/regex`, `elm/file`, `elm/bytes`, `elm/http`, `elm/random`, `elm/url`, `elm/json`, `elm/parser`, `elm/virtual-dom`,

        `elm/html`, `elm/svg`, `elm/browser`, `elm/time`, `elm-explorations/markdown`, `elm-explorations/webgl`, `elm-explorations/benchmark`, `elm-explorations/linear-algebra`

    -   `Platform`, `Platform.Cmd`, `Platform.Sub`, `Task`, `Process`

    -   **record update**, currying, ports, glsl, the prefix operator functions `(>>)` and `(<<)`

    -   `++` will default to `List.append` unless one of the arguments is a string literal. So e.g. use `a ++ b ++ ""` to append string variables (which is also faster in elm)

    - `List.minimum`, `List.maximum`, `List.sort`, `Basics.min`, `Basics.max` will only work for number lists.

    -   potential future candidates: `Basics.clamp`, `Basics.degrees`, `Basics.turns`,

        `Basics.radians`, `Basics.logBase`, `Basics.toPolar`, `Basics.fromPolar`, `Basics.never`, `Basics.sin`, `Basics.cos`, `Basics.tan`, `Basics.asin`, `Basics.acos`, `Basics.atan`, `Basics.atan2`, `Basics.e`, `Basics.pi`, `List.map5`, `List.map4`, `Char.toLocaleLower`, `Char.toLocaleUpper`, `Char.isAlpha`, `Char.isAlphaNum`, `Char.isDigit`, `Char.isOctDigit`, `Char.isHexDigit`, `List.map3/4/5`, `List.sortBy`, `List.head`, `List.tail` `Bitwise`, `Array`. Any help appreciated!

-   no checks are performed before transpiling to gleam. So if you don't add a compile check of your elm input,

    you might e.g. get a running program that circumvents an elm opaque type or phantom type, or a gleam program that can't be run

-   not much care has been put into making the resulting code readable or even conventionally formatted

    and comments are not preserved

Please [report any issues](https://github.com/lue-bird/elm-syntax-to-gleam/issues/new) you notice <3

### why gleam?

-   it's pretty much a superset of elm which makes transpiling easy