PySh 
Yet another shell can run anywhere Python exists.
Why another shell
Because it's fun.
Supported shell feature
Common shell features can be found here. Pysh already have:
|, Pipe output$var, Use value for variable" ", Double quote (allows variable and command expansion)*, Match any character(s) in filename?, Match single character in filename[ ], Match any characters enclosed
Usage
git clone https://github.com/jiacai2050/pysh.git
cd pysh
python -m pysh.shell
## Demo
> ls README*
README.md
> ls README.??
README.md
> echo $HOME
/Users/liujiacai
> echo ${JAVA_HOME}
/Library/Java/JavaVirtualMachines/jdk1.8.0_40.jdk/Contents/Home
> pwd
/Users/liujiacai/codes/python/pysh
> cd ..
/Users/liujiacai/codes/python
> pwd
/Users/liujiacai/codes/python
> cat /etc/hosts | grep 127.0.0.1
127.0.0.1 localhost
> grep 127.0.0.1 /etc/hosts
127.0.0.1 localhost
Supported commands can be found here.
More commands are on the way. PR welcomed !
Have fun
How PySh work
A shell in unix box is a bridge bewteen user and the kernel through system call.
As we can see from above picture (taken from here), some commands (eg ls, cat) are passed to other programs, while built-in commands (eg cd, exit) are executed inside shell. This way can keep shell small in size and strong in function.
In order to let PySh run anywhere (hi, Windows, I mean you), PySh implmented all commands in its core, so there is no differences bewteen builtins and one that is not, also you can say all commands are builtins.
One thing I should mention here is:
Pipelines between commands are supported by generator in Python.
So, every command should yield something, this is like s-expression in Lisp world, where every s-expression should return a value.
How to contribute
PySh use pre-commit to ensure code quality, so you should install it before contribute.
Fork and PR
TODO
- redirection
- wildcarding
- here documents
- command substitution
- variables
- control structures for condition-testing and iteration
- more useful commands
- curl
- wget
- sed
License
MIT License © Jiacai Liu
PySh is inspired from yosh.
