agatan / ncurses.cr

NCurses bindings for Crystal

ncurses

ncurses.cr is a Crystal binding to the C ncurses library.

Installation

Add this to your application's shard.yml:

dependencies:
  ncurses:
    github: agatan/ncurses.cr

You also need to install the ncurses library. e.g. in ubuntu, sudo apt install libncursesw5-dev

Usage

require "ncurses"

NCurses.open do
  # initialize
  NCurses.cbreak
  NCurses.noecho
  NCurses.start_color

  # define background color
  pair = NCurses::ColorPair.new(1).init(NCurses::Color::RED, NCurses::Color::BLACK)
  NCurses.bkgd(pair)

  NCurses.erase
  # move the cursor
  NCurses.move(x: 0, y: 1)
  # longname returns the verbose description of the current terminal
  NCurses.addstr(NCurses.longname)

  NCurses.move(x: 0, y: 2)
  NCurses.addstr(NCurses.curses_version)

  NCurses.move(y: 10, x: 20)
  NCurses.addstr("Hello, world!")
  NCurses.refresh

  NCurses.notimeout(true)
  NCurses.getch
end

Examples

See example/ for more examples.

Contributing

1. Fork it ( https://github.com/[your-github-name]/ncurses/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• agatan Naomichi Agata - creator, maintainer

ncurses.cr's Issues

clrtoeol

Where is clrtoeol?

The example colors.cr did not show anything on the terminal

I tried that:

crystal run example/colors.cr

and nothing happens at all!

Using Ubuntu 16.04 crystal 0.24.2

Please, add this to your readme:
https://stackoverflow.com/questions/26186824/how-to-install-the-ncursesw-development-libraries

KeyCode::ESC

Hi, would it be possible to add KeyCode for escpe?

Examples don't work on my laptop

Every example I try to run (except for mouse.cr) don't show anything. after a second or two the program terminates. no error is showing. echo $? return 0 so there is no error.

About my laptop:

$ lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 16.04.6 LTS
Release:	16.04
Codename:	xenial

---

$ uname -a
Linux oren 4.4.0-171-generic #200-Ubuntu SMP Tue Dec 3 11:04:55 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

Support for `-1` as a color

It looks like use -1 as a color number is supported to display no color. I'd like to be able to modify the code to allow that as a color pair value but it looks like it is only expecting unsigned integers. I don't have enough experience in Crystal to know how to fix this issue or I would have included it in #5.

An example of where this matters is when setting NCurses.use_default_colors. Since I'm forced to use a defined background color, it overwrites my default terminal background color. Is there a good way to fix this?

Without NCurses.use_default_colors

With NCurses.use_default_colors