PyShada can also be a slaver of a shell. It is shada.shhelper module. It serves a shell to provide the capabilities of defining and using Python commands for the users. All variables and commands are defined in a shared name space. The name space is persistent over the life of the shell. Everything you defined can be used over the time again and again, just like what you defined for the normal shell. It extents shell with Python.

How to Use shhelper?

After PyShada being installed, you can run following command to start shhelper.

eval `python -m shada.shhelper`

After that, you can see what Python commands is there with following command

$py cmds

You can also define variables in the Python name space.

$py set variable1 “value1”

And show it.

$py values

You can also define new Python commands. Following commands define a Python command to prefix every line, from stdin, a line number and write to stdout.

$py def lineno <<EOF
lno = 0
while True:
  yield
  line = session.recv()
  if line is None:
    break
  lno = lno + 1
  session.send('%04d %s' % (lno, line))
EOF

Then, you can try it

inkscape$ ls -l | $py lineno
0001 total 199376
0002 -rw-r--r--  1 thinker  user        699 Dec 21 23:12 Cython.muse
0003 -rw-r--r--  1 thinker  user        556 Nov 12 20:06 Cython.muse~
0004 -rw-r--r--  1 thinker  user      64209 Dec 27 13:06 FSM-n-action.png
0005 -rw-r--r--  1 thinker  user      44086 Dec 27 12:37 FSM-n-action.svg
0006 -rw-r--r--  1 thinker  user        667 Mar 25 15:59 NRArenaItem.muse
0007 -rw-r--r--  1 thinker  user        350 Mar 23 10:03 NRArenaItem.muse~
0008 -rw-r--r--  1 thinker  user        350 Mar 24 12:43 SPCanvasItem.muse
0009 -rw-r--r--  1 thinker  user        156 Mar 23 11:26 SPDesktopWidget.muse
0010 -rw-r--r--  1 thinker  user         89 Mar 23 11:25 SPDesktopWidget.muse~
0011 -rw-r--r--  1 thinker  user         94 Mar  4 20:33 SPNamedView.muse
0012 -rw-r--r--  1 thinker  user        749 Mar 28 01:03 SPObject.muse
0013 -rw-r--r--  1 thinker  user         90 Mar 25 18:11 SPObject.muse~
0014 drwxr-xr-x  3 thinker  user        512 Apr  1 19:53 arch
0015 drwxr-xr-x  2 thinker  user       1536 Nov  7 18:51 arch-html
0016 -rw-r--r--  1 thinker  user       1303 Mar  4 17:16 build_extension.muse
0017 -rw-r--r--  1 thinker  user        670 Jan 14 00:12 build_extension.muse~
0018 -rw-r--r--  1 thinker  user      36475 Nov  8 09:55 first-dock.png
0019 -rw-r--r--  1 thinker  user       4412 Nov  8 10:05 first-dock.svg
0020 -rw-r--r--  1 thinker  user      45684 Nov  8 10:05 first-dock.svg.png
0021 -rw-------  1 thinker  user  203763712 Dec 28 10:41 inkscape.core
0022 -rw-r--r--  1 thinker  user        255 Mar 31 12:02 inkview.muse
0023 -rw-r--r--  1 thinker  user         77 Mar 31 11:31 inkview.muse~
0024 -rw-r--r--  1 thinker  user       2251 Mar 23 16:12 main.muse
0025 -rw-r--r--  1 thinker  user       2143 Mar  4 20:26 main.muse~
0026 -rw-r--r--  1 thinker  user        685 Jan 26 22:56 pygobject.muse
0027 -rw-r--r--  1 thinker  user        480 Nov  8 18:23 pygobject.muse~
0028 -rw-r--r--  1 thinker  user      16248 Nov  2 09:22 wantyou.svg
inkscape$ 

Following is an example of random number generator.

inkscape$ $py def random <<EOF
import random
v = random.random()
session.send(str(v) + '\n')
EOF

command random was defined
inkscape$ $py random
0.217115667522
inkscape$ echo `$py random`
0.969004678594
inkscape$ 

Easy To Be Used!

shada.shhelper is easy to be used. It is a complement of shell commands. Sometime, shell is just not good for some kind of task, and Python is just good in these categories of work. shada.shhelper integrates Python into shell to make the life of shell easy.