This is a simple regular expression (RegEx) algorithm developed with python.

It supports:

• Literals ( abc )
• Ranges ( [a-z], [A-Z], [0-9], [a-zA-Z0-9] )
• Alternatives ( a|b )
• Matching in the middle of a string

To run a string against the regular expression, create a new object of RegEx with the expression or the pattern as its parameter.

Then by using the match function of the RegEx object pass the string as its parameter and get the result.

    from regex import RegEx

    re = RegEx("[a-z0-9]@[a-z].(com|net|org)")
    
    result = re.match("hello99@gmail.com") 
    # output: True

    result = re.match("Hello99@gmail.com") 
    # output: False

    result = re.match("Hello99@gmailcom") 
    # output: False

There are some test cases in tests.py file. Use the below code to run the test cases.

python tests.py