joaomoreno / vscode-ocaml-platform

Visual Studio Code extension for OCaml

VSCode OCaml Platform

Visual Studio Code extension for OCaml and relevant tools.

Please report any bugs you encounter.

Quick start

1. Install this extension from the VSCode Marketplace (or by entering ext install ocamllabs.ocaml-platform at the command palette Ctrl+Shift+P (Cmd+Shift+P on MacOS)
2. Open a OCaml/ReasonML project (File > Add Folder to Workspace...)
3. Install OCaml-LSP with opam or esy. E.g. opam install ocaml-lsp-server

Windows

Install OCaml for Windows and make sure the ocaml-env program is accessible on the PATH (ocaml-env is in the usr/local/bin folder relative to the installation directory).

ReScript / BuckleScript

The new ReScript syntax (res and resi files) is not supported, you should use rescript-vscode instead.

ReasonML, as an alternative syntax for OCaml, is supported out-of-the-box, as long as reason is installed in your environment.

If you're looking for a way to use OCaml or ReasonML syntax in a ReScript project, you'll need to install ocaml-lsp in your environment. We recommend using Esy for this:

1. Install esy

npm install esy --global

2. Add esy.json to the project root with following content:

{
  "dependencies": {
    "@opam/ocaml-lsp-server": "*",
    "@opam/ocamlfind-secondary": "*",
    "@opam/reason": "*",
    "ocaml": "4.6.x"
  }
}

3. Install and build packages

esy

Features

• Syntax highlighting
  • ATD
  • Cram tests
  • Dune
  • Menhir
  • Merlin
  • META
  • OASIS
  • OCaml
  • OCamlbuild
  • OCamlFormat
  • OCamllex
  • opam
  • ReasonML
  • Eliom
• Indentation rules
• Snippets
  • Dune
  • OCaml
  • OCamllex
• Task Provider
  • Dune

Configuration

This extension provides options in VSCode's configuration settings. You can find the settings under File > Preferences > Settings.

Name	Description	Default
ocaml.sandbox	Determines where to find the sandbox for a given project	null
ocaml.dune.autoDetect	Controls whether dune tasks should be automatically detected.	true
ocaml.trace.server	Controls the logging output of the language server. Valid settings are off, messages, or verbose.	off
ocaml.useOcamlEnv	Controls whether to use ocaml-env for opam commands from OCaml for Windows.	true
ocaml.terminal.shell.linux	The path of the shell that the sandbox terminal uses on Linux	null
ocaml.terminal.shell.osx	The path of the shell that the sandbox terminal uses on macOS	null
ocaml.terminal.shell.windows	The path of the shell that the sandbox terminal uses on Windows	null
ocaml.terminal.shellArgs.linux	The command line arguments that the sandbox terminal uses on Linux	null
ocaml.terminal.shellArgs.osx	The command line arguments that the sandbox terminal uses on macOS	null
ocaml.terminal.shellArgs.windows	The command line arguments that the sandbox terminal uses on Window	null
ocaml.repl.path	The path of the REPL that the extension uses	null
ocaml.repl.args	The REPL arguments that the extension uses	null

If ocaml.terminal.shell.* or ocaml.terminal.shellArgs.* is null, the configured VSCode shell and shell arguments will be used instead.

If ocaml.repl.path or ocaml.repl.args is null, the default REPL is used instead. The default REPL used depends on the packages installed in your current sandbox:

• If dune build passes and the current sandbox has utop installed, the REPL will be dune utop
• If dune build fails and the current sandbox has utop installed, the REPL will be utop
• Else, the REPL will be ocaml

If a REPL already exists, it will be used instead, so if you installed utop after openning a REPL, or if you fixed your project compilation, you will need to re-open the REPL to change it.

Commands

You can execute it by entering the following command at the command palette Ctrl+P (Cmd+Shift+P on MacOS).

Name	Description	Keyboard Shortcuts	Menu Contents
ocaml.select-sandbox	Select sandbox for this workspace
ocaml.server.restart	Restart language server
ocaml.open-terminal	Open a terminal (current sandbox)
ocaml.open-terminal-select	Open a terminal (select a sandbox)
ocaml.current-dune-file	Open Dune File (located in the same folder)
ocaml.switch-impl-intf	Switch implementation/interface	Alt+O
ocaml.open-repl	Open REPL
ocaml.evaluate-selection	Evaluate Selection	Shift+Enter

Requirements

• ocaml/ocaml-lsp