Networking: How To Communicate Between Two Python Programs.

Networking: How To Communicate Between Two Python Programs.

Networking is a huge field, so we’ll stick to the level concept that are important for programming. This is basically a beginner intro to networking. I am passionate about security and as I was reading and watching videos, I decided to write and share out this. So, networking is basically the concept of communicating across a… Continue Reading Networking: How To Communicate Between Two Python Programs.

how to create your own DSL(Domain Specific Language) in python

how to create your own DSL(Domain Specific Language) in python

Sometimes you need more than a cli program. You need more flexibility and control. A Domain Specific Language (DSL) is the right fit for specialised tasks. This post shows how you can build your own. Some rough notes/planning :

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aim : calculate cost of houses
 
input :
num of houses
price of house
 
output :
price of houses
 
technical tasks :
show to screen
 
--- file ---
 
house num 1,000
house price 250,000
calculate sum
 
--- output ---
 
$ 250 000 000

the code

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# py 3.7
import locale
 
source = '''
# calculates price of houses
house num 100
house price 250,000
calculate price
'''
 
def calculate(houses, unit_price):
    calc_price = houses * unit_price
    return calc_price
 
def output(price):
    # $ 250 000
    locale.setlocale(locale.LC_ALL, '')
    return f'{locale.currency(price, grouping=True)}'
 
def sanitise_price(price):
    # 250,000 -> 250 000
    return int(price.replace(',', ''))
 
def parse(source):
    houses = 0
    unit_price = 0
    calc_price = 0
    lines = [i for i in source.split('\n') if i]
    for line in lines:
        # simplification
        tokens = line.split()
        # comment
        if tokens[0] == '#':
            continue
        # commands
        elif tokens[0] == 'house':
            if tokens[1] == 'num':
                houses = sanitise_price(tokens[2])
            elif tokens[1] == 'price':
                unit_price = sanitise_price(tokens[2])
        elif tokens[0] == 'calculate' and tokens[1] == 'price':
            calc_price = calculate(houses, unit_price)
            print(output(calc_price))
 
parse(source)

you must  modify it to read from file last words it might… Continue Reading how to create your own DSL(Domain Specific Language) in python

venv usage on windows, activate and deactivate

venv usage on windows, activate and deactivate

go on to your project root directory first create a virtual environment with syntax python3 -m venv <env-name>

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python3 -m venv niceproject

a folder called niceproject will be automatically cd into <projectname>

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cd niceproject

then in the Scripts folder

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cd Scripts

then just type

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activate

it will activate as there is an activate.bat in the Scripts folder pip install what… Continue Reading venv usage on windows, activate and deactivate

Mastering Python’s Regex – part 1 : Basics

Mastering Python’s Regex – part 1 : Basics

Python regular expressions is often an overlooked topic in the python apprentice path due to it’s seemingly mingled nature. If programming was new enough, you don’t need those bizarre symbols to complicate your life further. However, if you understand it, you can use it. Regex is easy … if you get the right tutorial !… Continue Reading Mastering Python’s Regex – part 1 : Basics