Swift layer

Table of ContentsClose

1. Description
- 1.1. Features:
2. Install
3. Configuration
4. Key bindings
- 4.1. REPL
- 4.2. In REPL Mode

1. Description

This layer adds support for Apple's Swift programming language, used as a general purpose scripting language.

1.1. Features:

Auto-completion (with the lsp layer and sourcekit-lsp)
Syntax checking with flycheck (available with the syntax-checking layer)
Syntax highlighting with swift-mode
Indentation
Code navigation using imenu (built-in)

2. Install

To use this configuration layer, add it to your ~/.spacemacs. You will need to add swift to the existing dotspacemacs-configuration-layers list in this file.

3. Configuration

All layer configurations can be done by setting layer variables in your dotfile. No custom user config lines are necessary

3.1. Choosing a backend

This layer heavily relies on sourcekit-lsp to support proper IDE support. If the lsp layer is not available no auto-completion can be provided.

3.1.1. LSP

For proper IDE support this backend should be used. It is based on an external server which will be started automatically by emacs, once a swift file is opened. The key bindings are the same for all lsp modes so if you are already familiar with one you should be able to work the same in all modes.

To set explicitly do the following in your dotfile:

(swift :variables
        swift-backend 'lsp
        swift-lsp-executable-path "/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/sourcekit-lsp")

If this var is not set it will be set to lsp if the lsp layer is loaded.

For the system to work you will also need the latest version of the lsp server from sourcekit-lsp or directly from your Xcode installation. The path to the server executable must be given in the layer variable swift-lsp-executable-path.

NOTE: Key bindings for LSP are defined in the LSP layer. Also it is advisable to have a look at the autocomplete layer for an optimal intellisense config for LSP.

3.1.2. No lsp

In this case no specific config is necessary, but autocompletion will not be available.

3.2. Validation steps

First check that you are able to run this from the command line:

xcrun swift

Then validate that your lsp server is available under the given path if you are using lsp.

3.3. REPL integration

Unless configured by the user, the REPL will be invoked using the command

xcrun swift

You can launch the REPL directly from emacs with using the key binding SPC m s s (or C-c C-z). The universal prefix SPC u (C-u) may be used to modify command invocation.

4. Key bindings

4.1. REPL

Key bindings	Description
`SPC m '`	`swift-mode-run-repl` will run or switch to an existing REPL
`SPC m s s`	`swift-mode-run-repl` will run or switch to an existing REPL
`SPC m s b`	Send the current buffer to the repl
`SPC m s r`	Send the current region to the repl

4.2. In REPL Mode

Key bindings	Description
`SPC m s s`	swift-repl-mode-switch-back
`C-c C-z`	swift-repl-mode-switch-back