/lua-term

Terminal operations for Lua

Primary LanguageLuaMIT LicenseMIT

Overview

lua-term is a Lua module for manipulating a terminal.

Installation

lua-term is available on Luarocks.

OpenBSD

lua-term is available as an OpenBSD package. Use the proper Lua flavour to get the package for your Lua version:

# For Lua 5.1
$ doas pkg_add -r lua-term
# For Lua 5.2
$ doas pkg_add -r lua52-term
# For Lua 5.3
$ doas pkg_add -r lua53-term

Or install from ports:

$ cd /usr/ports/devel/lua-term
$ env FLAVOR=lua51 doas make install

openSUSE

lua-term is available in the devel:languages:lua devel project on OBS.

Add the repository and install lua-term via:

zypper addrepo http://download.opensuse.org/repositories/devel:/languages:/lua/openSUSE_Tumbleweed/devel:languages:lua.repo
zypper refresh
zypper in lua-luaterm

Adjust the repository URL to your version of openSUSE by substituting openSUSE_Tumbleweed with your actual version eg opensSUSE_42.2.

Windows

lua-term works on Windows as well when virtual terminal processing is enabled. To have this enabled automatically ensure that LuaSystem is installed (version 0.4.0 or newer). If found, that module will be used to enable virtual terminal processing and to switch output to utf-8.

Usage

    local term   = require 'term'
    local colors = term.colors -- or require 'term.colors'

    print(term.isatty(io.stdout)) -- true if standard output goes to the terminal

    print(colors.red 'hello')
    print(colors.red .. 'hello' .. colors.reset)
    print(colors.red, 'hello', colors.reset)

    -- The following functions take an optional IO handle (like io.stdout);
    -- io.stdout is the default if you don't specify one
    term.clear()    -- clears the screen
    term.cleareol() -- clears from the cursor to the end of the line
    --term.cursor.goto(1, 1) -- It will fail in Lua >= 5.2 because goto is a reserved word.
    term.cursor['goto'](1, 1) -- This will work on Lua >= 5.2, please use jump instead
    term.cursor.jump(1, 1) -- jump is just an alias for goto
    term.cursor.jump(io.stdout, 1, 1)
    term.cursor.goup(1)
    term.cursor.godown(1)
    term.cursor.goright(1)
    term.cursor.goleft(1)
    term.cursor.save()    -- save position
    term.cursor.restore() -- restore position

term Functions

Some functions in lua-term take an optional file handle argument; if this is not provided, io.stdout is used.

term.clear([opt_file])

Clear the terminal's contents.

term.cleareol([opt_file])

Clear from the current cursor position to the end of the current line.

term.isatty(file)

Returns true if file is a TTY; false otherwise.

NOTE: This function has been deprecated in favor of luasystem's implementation (or luaposix if you don't need Windows support). If you would like this functionality in the future, please use luasystem.

term.colors Values

The following values are available in term.colors:

Terminal Attributes

  • reset
  • clear (a synonym for reset)
  • default (a synonym for reset)
  • bright
  • dim
  • underscore
  • blink
  • reverse
  • hidden

Foreground Colors

  • black
  • red
  • green
  • yellow
  • blue
  • magenta
  • cyan
  • white

Background Colors

  • onblack
  • onred
  • ongreen
  • onyellow
  • onblue
  • onmagenta
  • oncyan
  • onwhite

Every value in term.colors may be used in several ways:

As a Function

print(colors.red 'hello')

As a String

print(colors.red .. 'hello' .. colors.reset)
print(colors.red, 'hello', colors.reset)

term.cursor Functions

term.cursor.goto([opt_file], x, y)

Place the cursor at (x, y).

term.cursor.jump([opt_file], x, y)

An alias for term.cursor.goto.

term.cursor.goup([opt_file], nlines)

Moves the cursor up nlines lines.

term.cursor.godown([opt_file], nlines)

Moves the cursor down nlines lines.

term.cursor.goright([opt_file], ncols)

Moves the cursor right ncols columns.

term.cursor.goleft([opt_file], ncols)

Moves the cursor left ncols columns.

term.cursor.save([opt_file])

Saves the cursor position.

term.cursor.restore([opt_file])

Restores the cursor position.

Alternatives

If you are looking to simply provide coloration to a terminal application and would like to use a more "tag-like" API (ex. colors '%{red}hello%{reset}'), there is a Lua rock named ansicolors: https://github.com/kikito/ansicolors.lua