mach.py 0.1.2

Features

• Get your CLI interfaces quickly

• Turn a simple class to a CLI application or an interactive interpreter.

Given:

class Calculator:

    def add(self, a, b):
        """adds two numbers and prints the result"""
        return a + b

    def div(self, a, b):
        """divide one number by the other"""
        return a / b

You can make command line application using the decorator mach1:

from mach import mach1

@mach1
class Calculator:

    def add(self, int: a, int: b):
        """adds two numbers and prints the result"""
       print(a + b)

    def div(self, int: a, int: b):
        """divide one number by the other"""
       print(a / b)


calc = Calculator()

calc.run()

Now if you run the module, you will get a program that you can invoke with the flag -h or --help:

$ python calc.py -h
usage: calc.py [-h] {add,div} ...

positional arguments:
{add,div}   commands

   add       adds two numbers and prints the result
   div       divide one number by the other

optional arguments:
  -h, --help  show this help message and exit

each method is a subcommand, with type checking and it’s own very help. Hench, this won’t work:

$ python calc.py add foo bar
usage: calc.py add [-h] b a
calc.py add: error: argument b: invalid int value: 'foo'

And this will:

$ python calc.py add 4 9
13

To see the help of the subcommand use -h:

$ python calc.py add -h
usage: calc.py add [-h] b a

positional arguments:
 b
 a

optional arguments:
  -h, --help  show this help message and exit

With the help of the decorator mach2 you can turn your class to CLI application and have also an iteractive shell which invoke when no parameters are given:

$ ./examples/calc2.py
Welcome to the calc shell. Type help or ? to list commands.

calc2 > ?

Documented commands (type help <topic>):
========================================
add  div  exit  help

calc2 > help add
adds two numbers and prints the result
calc2 > add 2 4
6
calc2 > div 6 2
3.0
calc2 > exit
Come back soon ...
$