Decorators - Exercise

# Decorators - Exercise

============================================================================

#01. Logged

def logged(func_ref):
    def wrapper(*args):
        func_result = func_ref(*args)
        return f'you called {func_ref.__name__}{args}\nit returned {func_result}'

    return wrapper


@logged
def func(*args):
    return 3 + len(args)


print(func(4, 4, 4))


@logged
def sum_func(a, b):
    return a + b


print(sum_func(1, 4))
============================================================================

# 02. Even Parameters

def even_parameters(func_ref):
    def wrapper(*args):
        for arg in args:
            if not isinstance(arg, int) or arg % 2 != 0:
                return "Please use only even numbers!"
        return func_ref(*args)

    return wrapper


@even_parameters
def add(a, b):
    return a + b


print(add(2, 4))
print(add("Peter", 1))


@even_parameters
def multiply(*nums):
    result = 1
    for num in nums:
        result *= num
    return result
============================================================================

# 03. Bold, Italic, Underline

def make_underline(func_ref):
    def wrapper(*args):
        func_result = func_ref(*args)
        return f'<u>{func_result}</u>'
    return wrapper


def make_italic(func_ref):
    def wrapper(*args):
        func_result = func_ref(*args)
        return f'<i>{func_result}</i>'
    return wrapper


def make_bold(func_ref):
    def wrapper(*args):
        func_result = func_ref(*args)
        return f'<b>{func_result}</b>'
    return wrapper


@make_bold
@make_italic
@make_underline
def greet(name):
    return f"Hello, {name}"


print(greet("Peter"))


@make_bold
@make_italic
@make_underline
def greet_all(*args):
    return f"Hello, {', '.join(args)}"
============================================================================

# 04. Type Check

def type_check(type_):
    def decorator(func_ref):
        def wrapper(param):
            if not isinstance(param, type_):
                return 'Bad Type'
            return func_ref(param)

        return wrapper

    return decorator


@type_check(int)
def times2(num):
    return num * 2


print(times2(2))
print(times2('Not A Number'))


@type_check(str)
def first_letter(word):
    return word[0]
============================================================================
# 05. Cache

def cache(func_ref):
    log = {}

    def wrapper(num):
        if num in log:
            return log[num]
        result = func_ref(num)
        log[num] = result

        return result

    wrapper.log = log
    return wrapper


@cache
def fibonacci(n):
    if n < 2:
        return n
    return fibonacci(n - 1) + fibonacci(n - 2)
============================================================================

# 06. HTML Tags

def tags(tag_name):
    def decorator(func_ref):
        def wrapper(*args):
            func_res = func_ref(*args)
            return f'<{tag_name}>{func_res}</{tag_name}>'

        return wrapper

    return decorator


@tags('p')
def join_strings(*args):
    return "".join(args)


print(join_strings("Hello", " you!"))