Python Coding challenge - Day 588| What is the output of the following Python Code?

Code Explanation:

 1. Defining the Decorator negate

def negate(f):

    def w(x): return -f(x)

    return w

negate(f) is a decorator function.

It takes a function f as input.

Inside it, w(x) is defined, which:

Calls f(x) (the original function),

Negates its result (i.e., multiplies it by -1).

Finally, it returns the wrapper function w.

 Purpose: This decorator flips the sign of any function’s output.

2. Applying the Decorator with @negate

@negate

def pos(x): return x + 5

This is shorthand for:

def pos(x): return x + 5

pos = negate(pos)

So, the original pos(x) which returned x + 5 is now wrapped.

The wrapped version will return -(x + 5) instead.

3. Calling the Decorated Function

print(pos(3))

This calls the decorated version of pos with input 3.

Internally:

pos(3) → w(3) → -f(3) → -(3 + 5) → -8

Final Output

-8

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