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.. image:: https://img.shields.io/travis/erikrose/blessings.svg
:alt: Travis Continous Integration
:target: https://travis-ci.orgerikrose/blessings/
.. image:: https://img.shields.io/teamcity/http/teamcity-master.pexpect.org/s/Blessings_BuildHead.png
:alt: TeamCity Build status
:target: https://teamcity-master.pexpect.org/viewType.html?buildTypeId=Blessings_BuildHead&branch_Blessings=%3Cdefault%3E&tab=buildTypeStatusDiv
.. image:: https://coveralls.io/repos/erikrose/blessings/badge.png?branch=master
:alt: Coveralls Code Coverage
:target: https://coveralls.io/r/erikrose/blessings?branch=master
.. image:: https://img.shields.io/pypi/v/blessings.svg
:alt: Latest Version
:target: https://pypi.python.org/pypi/blessings
.. image:: https://pypip.in/license/blessings/badge.svg
:alt: License
:target: http://opensource.org/licenses/MIT
.. image:: https://img.shields.io/pypi/dm/blessings.svg
:alt: Downloads
:target: https://pypi.python.org/pypi/blessings
Introduction
============
Blessings is a thin, practical wrapper around terminal capabilities in Python.
Coding with *Blessings* looks like this... ::
from blessings import Terminal
t = Terminal()
print(t.bold('Hi there!'))
print(t.bold_red_on_bright_green('It hurts my eyes!'))
with t.location(0, t.height - 1):
print(t.center(t.blink('press any key to continue.')))
with t.keystroke_input():
inp = t.keystroke()
print('You pressed ' + repr(inp))
Brief Overview
--------------
*Blessings* is a more simplified wrapper around curses_, providing :
* Styles, color, and maybe a little positioning without necessarily
clearing the whole screen first.
* Works great with standard Python string formatting.
* Provides up-to-the-moment terminal height and width, so you can respond to
terminal size changes.
* Avoids making a mess if the output gets piped to a non-terminal:
outputs to any file-like object such as *StringIO*, files, or pipes.
* Uses the `terminfo(5)`_ database so it works with any terminal type
and supports any terminal capability: No more C-like calls to tigetstr_
and tparm_.
* Keeps a minimum of internal state, so you can feel free to mix and match with
calls to curses or whatever other terminal libraries you like.
* Provides plenty of context managers to safely express terminal modes,
automatically restoring the terminal to a safe state on exit.
* Act intelligently when somebody redirects your output to a file, omitting
all of the terminal sequences such as styling, colors, or positioning.
* Dead-simple keyboard handling: safely decoding unicode input in your
system's preferred locale and supports application/arrow keys.
* Allows the printable length of strings containing sequences to be
determined.
Blessings **does not** provide...
* Windows command prompt support. A PDCurses_ build of python for windows
provides only partial support at this time -- there are plans to merge with
the ansi_ module in concert with colorama_ to resolve this. `Patches welcome
<https://github.com/erikrose/blessings/issues/21>`_!
Before And After
----------------
With the built-in curses_ module, this is how you would typically
print some underlined text at the bottom of the screen::
from curses import tigetstr, setupterm, tparm
from fcntl import ioctl
from os import isatty
import struct
import sys
from termios import TIOCGWINSZ
# If we want to tolerate having our output piped to other commands or
# files without crashing, we need to do all this branching:
if hasattr(sys.stdout, 'fileno') and isatty(sys.stdout.fileno()):
setupterm()
sc = tigetstr('sc')
cup = tigetstr('cup')
rc = tigetstr('rc')
underline = tigetstr('smul')
normal = tigetstr('sgr0')
else:
sc = cup = rc = underline = normal = ''
# Save cursor position.
print(sc)
if cup:
# tigetnum('lines') doesn't always update promptly, hence this:
height = struct.unpack('hhhh', ioctl(0, TIOCGWINSZ, '\000' * 8))[0]
# Move cursor to bottom.
print(tparm(cup, height - 1, 0))
print('This is {under}underlined{normal}!'
.format(under=underline, normal=normal))
# Restore cursor position.
print(rc)
The same program with *Blessings* is simply::
from blessings import Terminal
term = Terminal()
with term.location(0, term.height - 1):
print('This is' + term.underline('underlined') + '!')
Further Documentation
---------------------
More documentation can be found at http://blessings.readthedocs.org/
Bugs, Contributing, Support
---------------------------
**Bugs** or suggestions? Visit the `issue tracker`_ and file an issue.
We welcome your bug reports and feature suggestions!
Would you like to **contribute**? That's awesome! We've written a
`guide <http://blessings.readthedocs.org/en/latest/contributing.html>`_
to help you.
Are you stuck and need **support**? Give `stackoverflow`_ a try. If
you're still having trouble, we'd like to hear about it! Open an issue
in the `issue tracker`_ with a well-formed question.
License
-------
Blessings is under the MIT License. See the LICENSE file.
.. _`issue tracker`: https://github.com/erikrose/blessings/issues/
.. _curses: https://docs.python.org/library/curses.html
.. _tigetstr: http://www.openbsd.org/cgi-bin/man.cgi?query=tigetstr&sektion=3
.. _tparm: http://www.openbsd.org/cgi-bin/man.cgi?query=tparm&sektion=3
.. _ansi: https://github.com/tehmaze/ansi
.. _colorama: https://pypi.python.org/pypi/colorama
.. _PDCurses: http://www.lfd.uci.edu/~gohlke/pythonlibs/#curses
.. _`terminfo(5)`: http://invisible-island.net/ncurses/man/terminfo.5.html
.. _`stackoverflow`: http://stackoverflow.com/
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