CHANGELOG.md

Changelog

Unreleased

Compiler

• Generated Erlang .app files now include external modules written in Elixir and Erlang. (LostKobrakai)

• HexDocs documentation of Gleam packages now uses the ExDocs search data model, allowing for global indexing of Gleam packages in HexDocs, and making Gleam packages discoverable through global search of HexDocs. (Diemo Gebhardt)

• Allow users to set the GLEAM_CACERTS_PATH environment variable to specify a path to a directory containing CA certificates to install Hex packages. (winstxnhdw)

• On the JavaScript target, bit array expressions and patterns no longer need to be byte aligned, and the bits segment type is now supported in patterns. (Richard Viney)

Build tool

• The build tool now supports Git dependencies. For example:

  [dependencies]
  gleam_stdlib = { git = "https://github.com/gleam-lang/stdlib.git", ref = "957b83b" }
  

  (Surya Rose)

Language server

• The language server now has the ability to jump to the type definition of any hovered value. (Giacomo Cavalieri)

• The language server now offers a code action to convert the first step of a pipeline to a regular function call. For example, this code:

  import gleam/list
  
  pub fn main() {
    [1, 2, 3] |> list.map(fn(n) { n * 2 })
  }

  Will be rewritten as:

  import gleam/list
  
  pub fn main() {
    list.map([1, 2, 3], fn(n) { n * 2 })
  }

  (Giacomo Cavalieri)

• The language server now offers a code action to convert a function call into a pipeline. For example, this code:

  import gleam/list
  
  pub fn main() {
    list.map([1, 2, 3], fn(n) { n * 2 })
  }

  Will be rewritten as:

  import gleam/list
  
  pub fn main() {
    [1, 2, 3] |> list.map(fn(n) { n * 2 })
  }

  You can also pick which argument is going to be piped. In this case:

  import gleam/list
  
  pub fn main() {
    list.map([1, 2, 3], fn(n) { n * 2 })
    //                   ^ If you put your cursor over here
  }

  The code will be rewritten as:

  import gleam/list
  
  pub fn main() {
    fn(n) { n * 2 } |> list.map([1, 2, 3], _)
  }

  (Giacomo Cavalieri)

• The Language Server now suggests a code action to generate a function to encode a custom type as JSON using the gleam_json package. For example:

  pub type Person {
    Person(name: String, age: Int)
  }

  Will become:

  import gleam/json
  
  pub type Person {
    Person(name: String, age: Int)
  }
  
  fn encode_person(person: Person) -> json.Json {
    json.object([
      #("name", json.string(person.name)),
      #("age", json.int(person.age)),
    ])
  }

  (Surya Rose)

• The Language Server now suggests a code action to inline a variable which is only used once. For example, this code:

  import gleam/io
  
  pub fn main() {
    let greeting = "Hello!"
    io.println(greeting)
  }

  Will be rewritten as:

  import gleam/io
  
  pub fn main() {
    io.println("Hello!")
  }

  (Surya Rose)

• The code action to generate a dynamic decoder for a custom type can now generate decoders for types with multiple variants. For example this code:

  pub type Person {
    Adult(age: Int, job: String)
    Child(age: Int, height: Float)
  }

  Becomes:

  import gleam/dynamic/decode
  
  pub type Person {
    Adult(age: Int, job: String)
    Child(age: Int, height: Float)
  }
  
  fn person_decoder() -> decode.Decoder(Person) {
    use variant <- decode.field("type", decode.string)
    case variant {
      "adult" -> {
        use age <- decode.field("age", decode.int)
        use job <- decode.field("job", decode.string)
        decode.success(Adult(age:, job:))
      }
      "child" -> {
        use age <- decode.field("age", decode.int)
        use height <- decode.field("height", decode.float)
        decode.success(Child(age:, height:))
      }
      _ -> decode.failure(todo as "Zero value for Person", "Person")
    }
  }

  (Surya Rose)

• The language server now suggests a code action to easily interpolate a value into a string. If the cursor is inside a literal string the language server will offer to split it:

  "wibble | wobble"
  //      ^ Triggering the action with the cursor
  //        here will produce this:
  "wibble " <> todo <> " wobble"

  And if the cursor is selecting a valid gleam name, the language server will offer to interpolate it as a variable:

  "wibble wobble woo"
  //      ^^^^^^ Triggering the code action if you're
  //             selecting an entire name, will produce this:
  "wibble " <> wobble <> " woo"

  (Giacomo Cavalieri)

Formatter

Bug fixes

• Fixed a bug where division and remainder operators would not work correctly in guards on the JavaScript target. (Surya Rose)

• Fixed a bug where the "Generate function" code action would ignore the provided labels. (Giacomo Cavalieri)

• Fixed a bug where the "Pattern match on argument" and "Pattern match on variable" code actions would not allow to pattern match on a private type used in the same module it's defined in. (Giacomo Cavalieri)

v1.8.1 - 2025-02-11

Bug fixes

• Fixed a metadata caching bug where accessors for opaque types could sometimes be used in other modules. (Louis Pilfold)