Wyvernscale Source Code Editor (wsedit)

Build Status:

Introduction

wsedit is a clean, intuitive terminal-based editor with CUA keybinds. It is designed to get the job done in a simple, elegant and pragmatic manner. If you've ever worked with a text editor and with a terminal, you already know how wsedit works, except some small quirks here and there maybe.

Features

• Dynamic dictionary-based autocompletion: Specify which files to index, and how (e.g. ignore comments, only global definitions, ...).

• Pragmatic syntax highlighting: Highlights keywords, strings, matching brackets and comments declared in your config files. Default patterns for some languages are availabe for import in lang/*.wsconf, writing your own should take no longer than 30 minutes, including the submission of a pull request on GitHub =).

• Character class highlighting: This will colour your text by character class (e.g. operators -> yellow, brackets -> brown, numbers -> red, ...). This supplements the already mentioned syntax highlighting quite nicely and provides a base-line readability boost if no highlighting rules have been set.

• Simple configuration interface via config files: Not really much to say here.

• Reader mode: Want to glance over a file without accidentally editing it? Start the editor in read-only mode, or toggle it via keybind.

• Protects you data: Special routines are in place to ensure your work doesn't just vanish, should the editor crash. I sure wish having this wasn't something to be proud of.

Platforms / Installation

Windows: not supported

As vty (wsedit's terminal I/O library) depends on unix which supports neither Cygwin nor MinGW, there's currently no way to build wsedit for Windows

Linux: build from source

No packages available yet, contact me if you want to package wsedit for your distribution.

OSX: Homebrew

Thanks to Alex Arslan for providing a homebrew formula for wsedit:

brew tap ararslan/pints
brew install wsedit

IMPORTANT: I have no access to OSX systems myself, so the amount of support I can provide for platform-specific issues will be heavily limited and I might need your help to test some things for me.

Building from source

"I know how to linux"

1. Install:

• stack,
• ncurses with unicode support,
• wl-clipboard, xclip or xsel, optional, makes wsedit use the system clipboard.

2. Grab the latest wsedit release off GitHub.
3. Run stack install, the binary will be placed into $HOME/.local/bin/.
4. Either add $HOME/.local/bin/ to your $PATH or copy/link/symlink the execuable where you actually want it.
5. Run ./install_lang.sh, as root if you want the definitions to be installed system-wide. If your favourite language has no definitions available, you can easily create them yourself, take a look at lang/README.md for instructions.
6. Done! I recommend opening two terminals next to each other, running wsedit in one of them and looking up keybinds in the other one with wsedit -hk. Alternatively, you can view the keybinds with F1.

"I'm new, please be gentle"

First of all, welcome to Linux! If you encounter any problems, take a look at the Troubleshooting section further down below and see if it helps.

1. Install the Haskell Tool Stack. (If you don't have root access to install stack, pick the Linux (general) option and call the stack binary inside the archive directly.)
2. Make sure you have ncurses with unicode support installed. This should be default on most popular distributions.
3. Optional, Linux only: Install either wl-clipboard, xclip or xsel with your package manager. If this step is skipped, wsedit will use a file buffer instead of the system facilities for copy/paste functionality.
4. Grab the latest stable release of wsedit from the Releases tab on GitHub.
5. Extract the archive and point your shell towards its contents.
6. Run stack setup to pull in the correct version of ghc.
7. Run stack install to build the dependencies and wsedit.
8. Check whether $HOME/.local/bin is already part of your $PATH variable: if the command echo "$HOME" | grep "$HOME/.local/bin" has no output, add the line PATH="${PATH}:${HOME}/.local/bin" to the file ~/.bashrc. This file will be executed every time you open a shell, so you either need to re-open the terminal or run source ~/.bashrc to re-run it manually.
9. To get syntax highlighting, run ./install_lang.sh. If you want them to be installed for all users, run sudo ./install_lang.sh instead. If your favourite language has no definitions available, you can easily create them yourself, take a look at lang/README.md for instructions.
10. Done! I recommend opening two terminals next to each other, running wsedit in one of them and looking up keybinds in the other one with wsedit -hk. Alternatively, you can view the keybinds with F1.

Bugs / Crashes and how to report them properly

Please submit every kind of weird behaviour you encounter as an issue on GitHub. If possible, obtain a state dump as described below.

A general note on the stability of wsedit

When I started development on WSEdit back in 2016, it would frequently break things in a way that causes data loss. Since then, a lot of data protection safeguards have been implemented, and the codebase has matured quite a bit. Nowadays many things have to go wrong at once for data to be damaged, and as a result of this, I haven't had data loss in years.

I originally planned to write an extensive test suite for WSEdit, but have since stopped working on that for a number of reasons:

• Writing anything but simple unit tests for an interactive editor is very hard,
• Expected impact for bugs will be very low since the editor seems to work well and multiple safety nets are in place,
• The editors with comparable scope that I've checked don't seem to have test suites either.

Considering all that, the limited time I have for working on WSEdit is better spent developing new features.

Crashes

The editor main loop runs inside an exception handler that will do the following:

1. Dump the current state of your file to ${HOME}/CRASH-RESCUE if it has been modified since the last save. As long as this location stays writeable, next to nothing can happen to your data.
2. Dump the editor's configuration, state and some additional info to ${HOME}/CRASH-DUMP. This file can be used to restart the editor in the last coherent state before it crashed.
3. Safely shut down everything.

The state dump is of great importance to fixing the bug. However, it contains all active configuration as well as the entire file you edited when the crash happened. Make sure you are okay with that becoming public before uploading it. Also, please do not provide a modified dump file, as any changes made will throw off the caching system.

Data corruption on save

By default, the editor saves data in the following way:

1. The contents are written to a new file.
2. The written file is immediately read again, and the result is compared to the current buffer. If these don't match, your current data is emergency-saved to ${HOME}/CRASH-RESCUE with conservative encoding settings, and the editor aborts.
3. The new file receives the same permissions as the old file.
4. The new file is atomically renamed over the old file.

This behaviour can be disabled, but it is highly recommended not to do so.

Non-fatal bugs

Most non-fatal bugs will probably be rendering glitches. Reproduce the situation, point the cursor at it if possible, then press F9. This will simulate a crash and create the above-mentioned files.

Known issues / Troubleshooting / FAQ

My cursor is invisible!

Deactivate the -db switch.

wsedit is slow (on older machines)!

• Disable -db if it is active.
• Performance is highly dependant on your terminal emulator. I can personally recommend termite, sakura, xterm and to a lesser degree also rxvt-unicode if you really hate yourself.

The build fails with some obscure error message

• Make sure all non-haskell dependencies listed above are satisfied.
• Try stack clean or maybe stack update.
• If that doesn't work, delete the .stack-work folder and try again.

wsedit destroys Unicode on xterm (sometimes)

Symptoms: After running wsedit, any unicode output by other programs (e.g. tree) will be garbled.

This seems to be a problem wit vty, the terminal library wsedit uses, since yi, another terminal editor based on vty, suffers from the same issue. For now I can only recommend using another terminal emulator if you need the unicode support.

Some inputs (e.g. Ctrl-Down) don't work in rxvt-unicode

Yeah, urxvt is a mess. I recommend switching to another terminal, but adding this to your .Xresources file will soothe your pain:

! From http://thedarnedestthing.com/urxvt
urxvt*keysym.C-Up: \033[1;5A
urxvt*keysym.C-Down: \033[1;5B
urxvt*keysym.C-Right: \033[1;5C
urxvt*keysym.C-Left: \033[1;5D
urxvt*keysym.S-Up: \033[1;2A
urxvt*keysym.S-Down: \033[1;2B
urxvt*keysym.S-Right: \033[1;2C
urxvt*keysym.S-Left: \033[1;2D
urxvt*keysym.M-Up: \033[1;3A
urxvt*keysym.M-Down: \033[1;3B
urxvt*keysym.M-Right: \033[1;3C
urxvt*keysym.M-Left: \033[1;3D

urxvt*iso14755: False
urxvt*iso14755_52: False

Licensing

The entire codebase, including the language definitions, is licensed under the 3-Clause BSD License, see LICENSE.