Printing a line by updating an already outputted line

Question

Hi everyone,

Forgive me if the title is not lucid, but I could not better describe it in a single sentence.

Consider I have the following in a loop, which increments counter each time it runs.

output_string = 'Enter the number [{0}]'.format(counter)

When I do a print output_string, the output goes like:

Enter the number [1]: 

When I print this line again with the incremented number, like:

Enter the number [2]:

It will of course follow the 1st line and the cumulative output would be:

Enter the number [1]:
Enter the number [2]:

However, I don't want this. I want the first line line should be updated and without adding another line, the output should just change in the first line itself.

Like, it should display Enter the number [1]: and after that it should do an in-place replacement for [1] and the screen should read: Enter the number [2], without adding an extra line.

I hope I am being clear. The reason I am doing this is because I am taking in large inputs from the user and I don't want to clutter up the terminal when I can just keep on incrementing what I want within a single line.

Answer 1

If your script will be running on Unix/Linux you could use the curses module.

Answer 2

Try this

print('enter the number[1]', end='\r' )

If you're using Python 2.7, don't forget from __future__ import print_function.