Lightweight Emacs

About

This is a "lightweight" emacs configuration focused on editing C/C++, Python, and Markdown. It's not that lightweight after I've added all the features that I want, but it's "lighter" than what I had, which was heavier than the average blue whale.

Why?

I decided to start working on a brand-new configuration after my previous one started to become really unwieldy/slow, along with the fact that I was getting tired of having a configuration that I didn't really fully understand. Additionally, I was tired of updating packages from MELPA that broke in newer versions or had changed in behaviour, and resulted in my configuration behaving slightly different across my different workstations (which was supposedly part of the reason why I switched to using Emacs in the first place).

Finally, I was tired of having my configuration dump a ton of stuff in my user folder. I wanted my configuration to all stay in a single directory, and not affect my existing Emacs installation or normal configuration.

What?

This configuration does not rely on MELPA or any external package manager. It is focused on using only the plugins I find useful instead of starting with a gazillion ones that Prelude installs, and writing my own functions for the rest of the functionality that I require.

Goals of this configuration:

• Optimized for C/C++/Python work, in that order. Some extra stuff like shaders (HLSL/GLSL), Maya support (through etom) and Maxscript support.
• Code completion and introspection through eglot.
• Able to run completely side-by-side with your existing Emacs installation and not dump any of its configuration files anywhere outside of the repository.
• (As far as possible) Immutable configuration; not dependent on package managers or changing versions of modules.
• Not much else, really. It's still almost as slow as my original config; but now it's at least a lot easier for me to figure out what's going on within the config file and fix/add things.
• Not intended to be a Sublime Text/VS Code/Atom replacement. In my mind, this is intended to be my go-to IDE for real work. I still use my crazy Vim config for normal text editing.

How?

Dependencies

You will need the following dependencies, regardless of your platform:

• Emacs 27.1 is the current supported version. No earlier versions are supported since native JSON support is a big thing.
• clang/llvm clangd is required for eglot.
• OmniSharp-roslyn Get the latest non-http release.
• On MacOS, you will need Xcode and Xcode command-line tools installed.
• grep
• gdb
• CMake
• Git
• ag (A.K.A. The Silver Searcher). A Windows version is available here.
• ripgrep This will eventually replace the need for ag.
• fd as a replacement for find. This is not required on macOS/Linux, but is faster anyway. On Windows this is required for projectile to invoke the right find command.
• GHCup For Haskell support.
• make for MSYS2 needs to be installed and available on the PATH.
• Support for black in Python using pip install --user black black-macchiato

Installation

Clone this repository with all its submodules first.

git clone --recursive <git-repo-url>

or:

git clone <git-repo-url>
git submodule init
git submodule update --recursive

You will also need to ensure that the HOME environment variable is set to your %USERPROFILE% folder as well.

Because haskell-mode requires a bit of generation, you need to navigate to the /modules/haskell-mode directory, and then run:

make EMACS=/path/to/your/emacs

On Windows, run that in a normal command prompt (not Cygwin or MinGW), and make sure that you run it in the haskell-mode subdirectory that is not part of a symbolic link.

Anyway, once everything is cloned and set up, you can run this side-by-side with your current Emacs installation if you just want to check it out using this method.

What I do is launch Emacs using this command:

emacs -q --load ~/Git/lightweight-emacs/lightweight_config.el

Set that as an alias or desktop file or whatever you prefer.

Setup

eglot is used for code completion. Thus,

• compile_flags.txt and compile_commands.json for C/C++ using clangd. This should be arguments given to clang directly. Sample:

-std=c++14 -Wall -Wextra -pthread -Wno-pragma-once-outside-header -Iinclude -I/home/sonictk/Qt5.8.0/5.8/gcc_64/include

* `C-u M-x eglot` in C# buffers and enter a `.sln` or `.csproj` file for OmniSharp.
(i.e. `OmniSharp.exe -lsp -s "C:\\path\\to\\solution.sln"`)

Sample ``.dir-locals.el`` file:

( (nil . ((tab-width . 4) (indent-tabs-mode . t)))

(c++-mode . ((c-basic-offset . 4) (tab-width . 4) (indent-tabs-mode . t) (compile-command . "cmake --build ./build --config Release --target INSTALL") (cd-compile-directory . "/home/sonictk/Git/project/build") ))

(c-mode . ((c-basic-offset . 4) (tab-width . 4) (indent-tabs-mode . t) (compile-command . "cmake --build ./build --config Release --target INSTALL") (cd-compile-directory . "/home/sonictk/Git/project/build") )) )

### Known issues

Get rid of the dumb warnings from some of the plugins by byte-compiling them.
Run the following command in the ``/modules`` folder:

``emacs -batch -f batch-byte-compile ./**/*.el``

Remember to re-run this every time you pull new modules from the repository, or
you'll be running outdated code!

### Most important non-standard keybinds

* ``C-,``/``C-.``: Finds the other header/implementation file in C/C++ modes in
  the same/other window.

* ``M-.`` : Go to defintion of symbol. Use ``C-S-M-n/p`` to navigate up/down in
  the candidate list. Use ``C-S-g`` to quit and return the cursor to where it
  was before invoking the goto command.

* ``M-n/p`` : Navigate line up/down while maintaining cursor position.

* ``C-M->``/``C-M-<``: Finds the header file at point. Needs the
  ``.dir-locals.el`` file set with the header search paths.

* ``C-c h i``/``C-<f12>``: Shows all symbols defined in the current file for
  C/C++/Python modes.

* ``S-<arrow key>``: Switch cursor to buffer in direction of arrow key

* ``M-S-<arrow key>``: Move buffer in direction of arrow key (will swap buffer
  in other window if it exists)

* ``C-w/M-w`` will delete/copy lines if no region is selected

* ``C-enter``/``C-S-enter``/``S-enter`` all insert/prepend newlines like other
  text editors do.

* ``C-c <C-left/C-right>``: Navigates to last/next cursor
  position globally

* ``C-c <left/right>``/``C-c b/f``: Navigates to last/next cursor position
  locally

* ``S-<mouse3>``: Start marking rectangle regions

* ``S-<mouse2>``: Toggle hiding/showing of regions

* ``C-S-v``: yank (paste)

* ``C-z``/``C-S-z``: undo/redo

* ``C-x >/<``: Scroll left/right

* ``C-tab``: Autocomplete (this uses ``irony-mode`` in C/C++ mode, Python uses
  ``elpy`` to do so)

* ``C-x m``/``C-x M-m``: Start Emacs shell/Normal shell

* ``C-M-S-w``: Toggle ``visual-line-mode`` (line wrapping)

* ``C-S-f``: Search using ``projectile-ag`` (The silver searcher). Way faster
  than ``grep``.

* ``C-S-b``: Run the ``cd-compile`` command to allow for building your project.

* ``C-S-s``: Toggle ``sr-speedbar``.

#### GDB mode

When using ``gdb``, additional keybinds become available while debugging:

* ``C-S-f8`` : Finish execution of the current function.
* ``f8`` : Step over.
* ``M-f5`` : Finish execution of the current program.
* ``f5`` : Continue.
* ``C-f8`` : Set a new breakpoint at the current cursor position.
* ``M-f8`` : Remove breakpoint from the current cursor position.
* ``C-f5`` : Continue till line at current cursor position.
* ``C-S-f7`` : Step into line.
* ``f7`` : Step into function call at cursor position.

There's a ton more, obviously, which you can dig through the config file to
find. Those are the mose important ones, though.

### Most important new commands

* ``reload-dir-locals-for-current-buffer`` : Does what it says. No more
  restarting Emacs!

* ``kill-other-buffers``: Does what it says. No more hitting ``C-x k`` 50
  times!


## Who?

Siew Yi Liang a.k.a. sonictk.

Tons of plugins are used in this configration; their licenses and original
source code have been preserved (except for some changes I made to
``back-button.el``, because it stomps default Emacs keybindings) Please kowtow
to them as appropriate if you end up using this configuration for their
kindness and benevolence.


## Whaaaaaa~?

Changes are being made constantly to this configuration, and I make no promises
that this won't break your installation or your heart. If it does...

¯\_༼ ಥ ‿ ಥ ༽_/¯

(Please report bugs, though I can't promise I'll fix them!)