Setting up Vala mode on Emacs - emacs

Question

I'm trying to set up a mode for editing Vala in Emacs. I've only found these instructions, and it seems that (for the first case with packages) marmalade no longer carries vala-mode, and for the second, csharp-mode always fails to compile when I try to install it! What should I do?

Answer 1

I just confirmed that vala-mode is not included in the marmalade archive, despite the link above. To work around this, from within M-x eshell execute:
$ wget http://marmalade-repo.org/packages/vala-mode-0.1.el
$ package-install-file vala-mode-0.1.el
package-install works with the network automatically, but package-install-file, and package-install-from-buffer are also available.
Of course this solution will not download it automatically going forward, so you should contact Marmalade maintainers to determine why it's not listing it in the archive, or possibly submit it for inclusion in Melpa.

Answer 2

Another useful thing you can do is install and configure an LSP language server. I've had some success with https://github.com/Prince781/vala-language-server.
You can then install lsp-mode (https://github.com/emacs-lsp/lsp-mode) and lsp-ui (https://github.com/emacs-lsp/lsp-ui) for Emacs.
And then create a compile_commands.json file for your Vala project. E.g.
[
{
"directory": "/home/user/projects/example",
"command": "/usr/bin/valac /home/user/projects/example/main.vala",
"file": "/home/user/projects/example/main.vala"
}
]
I haven't found an automatic way of doing this. But it's possible you could use CMake. CMake is definitely capable of generating a compile_commands.json. You would just need to describe your Vala project in a CMakeLists.txt file.
Then you add (lsp) to your vala-mode-hook:
(add-hook 'vala-mode-hook #'(lambda () (lsp)))