Can I have more than one function with the same name?

can we use functions with same name in single program?
in this case which function definition will be invoked when we called evaluate(10) second time.

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One function can be given many names, but many functions cannot have the same name. If we happen to declare two functions of the same name, the latter one in the source listing is the one that will apply.

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Thank you sir,clarified!

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It’s not strictly true, if the source code is not all executed sequentially. The def block that was processed most recently to define a particular function name is the one that applies when that name is used to call a function. See the following example:

import random

for i in range(4):
  choice = random.randint(1, 2)
  if choice == 1:
    print("defining first version of the_function.")
    def the_function():
      print("\nI am the first version of the_function!")

  if choice == 2:
    print("defining second version of the_function.")
    def the_function():
      print("\nI am the second version of the_function!!")

the_function()

Output from a sample run:

defining second version of the_function.
defining second version of the_function.
defining second version of the_function.
defining first version of the_function.

I am the first version of the_function!
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This seems more advanced than what the lessons have taught us up to this point.

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Hello @core1805653314, and welcome to the Codecademy Forums!

Yes, it is indeed more advanced than what the lessons have taught thus far. The example was provided in order to demonstrate an answer to this question:

While the provided example does address the question by demonstrating that we can redefine the name of an existing function, it is generally not a good idea to do so, unless there is a compelling reason for it. Such a technique can confuse programmers who read the code, and result in a buggy program. For that reason, Codecademy does not teach such a technique, at least as far as I am aware.

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But why not just stick with examples that fall within what has been learnt so far? I feel thats better considering your audience

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Sorry, it’s very interesting for me, means that a function call “can find” its function even in enother scope? Right?

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The scoping rules that apply to variables also apply to functions. We can define a function that is local to the scope of a function that contains it. However the outer function can return a reference to the local function that it contains. That would make the local inner function accessible to the outside, under a name chosen by the caller of the outer function. To arrange for that, just assign the returned function reference to a variable.

A function can even return references to multiple functions by including them in a returned list or dictionary.

We can experiment with examples upon request.

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Yes, PLEASE! It’s very interesting! Thank you in advance.

Here’s an example of a function factory that defines an inner polynomial evaluator function and returns it for use outside the function factory:

def polynomial_function_factory(coeffs):
  # coeffs: a list of polynomial coefficients
  
  # define customized polynomial function with coeffs built in
  def polynomial_function(x):
    # initialize the result accumulator
    result = 0
    # iterate through the coefficients
    for coeff in coeffs:
      # multiply result accumulator by x and add coefficient
      result = result * x + coeff
    # result is complete; return it
    return result
  
  # return the function definition
  return polynomial_function

# create the function by calling the factory; save as poly
poly = polynomial_function_factory([2, 4, 1])
# call the function
print(poly(1))
print(poly(2))
print(poly(3))

Output:

7
17
31
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Here’s a function factory that is recursive:

def power_function_factory(max_power):
  # return a list of power functions
  # with exponents from 0 to max_power, inclusive
  if max_power == 0:
    # base case
    return [lambda n: n ** 0]
  else:
    # recursive case
    return power_function_factory(max_power - 1) + [lambda n: n ** max_power] 

funcs = power_function_factory(7)

square = funcs[2]
cube = funcs[3]
fourth = funcs[4]

print(square(3))
print(cube(5))
print(fourth(2))

Output:

9
125
16
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Thank you very much for the exapmles!! It’s impressive, I’ll chew it for some time :slight_smile:

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Hello!
What could be the possible benefit of using this kind of design pattern over using less complex albeit longer, simpler function definitions?
How do you balance this with the principle of KISS (Keep it Simple, Stupid)?

Thank You

Hi, i am a bit lost in this chapter. The variable user_name was created after the function and the result could be printed out successfully. However, not sure in which previous chapter did mentioned that, Python read and run the system from top to bottom, so if the variable is not created before the function, logically it should not be printed out? (i am confused on this, please help)

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are we talking about the function parameter (user_name) on line 1?

Functions are a set of instructions which are executed later, as such, parameters don’t need to have a value yet. They act as placeholder

then when you call the function, you need to provide arguments for your parameters.

Hi @stetim94 . Thank you for your answer. i have solved this question after posting here. The reason i get confused is because the parameter having same name as the variable and i had accidentally neglect the function call out with the variable, not the parameter user_name.

Anyway, thank you for your kind answer!

Hi, I am confused with this exercise. Why did you use “def dave_check and return” if we have not seen that so far in the course. I understand that there are probably several ways of solving the problem but it doesn’t seem to be logic as we haven’t got yet the arguments to code all that.

This is what I did with what is in my opinion the arguments we have so far. It prints the message but it did not allow me to continue

Enter a user name here, make sure to make it a string

user_name= “Dave”

if user_name:
print(“Get off my computer Dave!”)

user_name1= “angela_catlady_87”

if user_name1:
print(“I know it is you Dave! Go away!”)

Thanks

That can be any string, as long it is not empty. The check might need to be more specific if you are actually targeting ‘Dave’.

if user_name == "Dave":

It will help if we have the exercise narrative and instructions. Please post a link to the exercise in a reply.

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Thanks for your reply,

https://www.codecademy.com/courses/learn-python-3/lessons/python-control-flow/exercises/if-statement

This is the link to the exercise.

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