Pass a list to a function instead of user-input

My function gets input from user. I want to call it in a way that it gets input from list - without changing function. I am using Jupyter notebook - Python

def example_function() :

 a = input()
 b = input()
 print (a b)
 c = input()
 d = input()
 print (c d)

 return

I want to call example_function and pass a list to it as input values (a, b, c and d). It is not possible to change example_function itself.

CodePudding user response：

You can do it by temporarily changing stdin which is where the input() function gets its data:

from contextlib import contextmanager
from io import StringIO
import sys


@contextmanager
def redirect_stdin(source):
    save_stdin = sys.stdin
    sys.stdin = StringIO('\n'.join(source) '\n')
    yield
    sys.stdin = save_stdin

def example_function():
    a = input()
    b = input()
    print(a b)
    c = input()
    d = input()
    print(c d)
    return


inp = ['a', 'b', 'c', 'd']

with redirect_stdin(inp):
    example_function()

Output:

ab
cd

CodePudding user response：

Try this:

def get_inputs():
  a = input()
  b = input()
  c = input()
  d = input()
  return (a, b, c, d)

def example_function(a, b, c, d):
  print(a   b)
  print(c   d)
  return

example_function(*get_inputs())

Or more literally what you asked for, passing a list:

def get_inputs():
  a = input()
  b = input()
  c = input()
  d = input()
  return [a, b, c, d]

def example_function(inputs):
  a = inputs[0]
  b = inputs[1]
  c = inputs[2]
  d = inputs[3]
  print(a   b)
  print(c   d)
  return

example_function(get_inputs())

CodePudding user response：

I guess it's necessary to change the function here because it doesn't have any arguments currently. Here's one way to do the function so it works like you described.

def example_function(list):

counter = 0
for i in list:
    counter = counter  1
    if (counter == 1 or counter == 3):
        print(list[i]   list[i -1])

CodePudding user response：

With absolutely no changes to your example_function function, the only way I'd know is to change the global input. You should also reset it after so that the rest of your script works. this can be done by creating another method.

def example_function():
  a = input()
  b = input()
  print (a b)
  c = input()
  d = input()
  print (c d)
  return

def call_example_function(list):
  global input
  _input = input
  index = 0
  def input(*args, **kwargs):
    nonlocal index
    ret = list[index]
    index  = 1
    return str(ret) # the normal input will always return a string
  example_function()
  input = _input

if __name__ == "__main__":
  name = input("What's your name?")
  print(name)
  call_example_function(["aa", "bb", "cc", "dd"])
  pet = input("What pet do you have") # input works as normal outside
  print(pet)

Output:

aabb
ccdd

Attempt This Online!