How Do Function Decorators Work, and How Can They Be Chained?

Function Decorators and Chaining

What are Function Decorators?

Decorators are functions that modify other functions. They provide a way to enhance or extend the behavior of a function without directly modifying it.

Syntax:

@decorator_function
def function_to_decorate():
    # Function body

Chaining Decorators

Decorators can be chained, meaning you can apply multiple decorators to the same function. The order in which you chain the decorators matters.

@decorator2
@decorator1
def function_to_decorate():
    # Function body

In this example, decorator1 will be applied first, followed by decorator2.

Example

To achieve the desired output, you can create custom decorators:

# Decorator for bolding text
def makebold(fn):
    def wrapper():
        return "<b>" + fn() + "</b>"
    return wrapper

# Decorator for italicizing text
def makeitalic(fn):
    def wrapper():
        return "<i>" + fn() + "</i>"
    return wrapper

@makebold
@makeitalic
def say():
    return "Hello"

print(say())  # Output: "<b><i>Hello</i></b>"

In this example, the @makebold decorator is applied first, followed by @makeitalic. The output is "Hello" enclosed in bold and italic tags.

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