Newbie Loop Question (Python)

[insomaniacal]

I think what he wants is for string "x" to be printed over and over while the computer waits for input from the user. So something like this...

Code: Select all

**Program Starts**
**Program starts waiting for user input**
**Program printing "x" until user input**
x
x
x
x
x
x
x
**user presses a key/types something**
y
Where "x" is the string he wants to be printing, and y is whatever happens after a user hits a key.


[tgoe]

Python 2x/3x input methods only block and won't work for this. I think you can make it work with the python curses bindings though. In particular the getch(), nodelay() and halfdelay() methods.

[Spectre557]

I think what he wants is for string "x" to be printed over and over while the computer waits for input from the user. So something like this...

Code: Select all

**Program Starts**
**Program starts waiting for user input**
**Program printing "x" until user input**
x
x
x
x
x
x
x
**user presses a key/types something**
y
Where "x" is the string he wants to be printing, and y is whatever happens after a user hits a key.


That's pretty much exactly what I was looking for, thanks for clarifying.

Python 2x/3x input methods only block and won't work for this. I think you can make it work with the python curses bindings though. In particular the getch(), nodelay() and halfdelay() methods.

I have no previous experience with those, so would you mind explaining them a little bit please?

[tgoe]

It's ugly but here goes... You basically have to treat the absence of input as an error, catch the error and then ignore it

Here's an animated prompt just to show that you can modify the screen while waiting for input:

Code: Select all

#!/usr/bin/env python

import curses

screen = curses.initscr()
inp = ""
word = "quit"

for i in range(10000):
    # modify the screen
    screen.clear()
    screen.addstr("Type 'quit' to quit: (" + inp + ") " + "!" * (i % 10) +"\n")
    screen.refresh()

    # collect input if present or throw an error
    try:
        curses.halfdelay(1)
        inp += chr(screen.getch())
    except:
        pass

    # use the input in some way
    if inp == word:
        break
    if len(inp) > len(word):
        inp = ""

curses.endwin()


Continously scrolling text would take a bit more work but the idea is the same.

[Spectre557]

It's ugly but here goes... You basically have to treat the absence of input as an error, catch the error and then ignore it

Here's an animated prompt just to show that you can modify the screen while waiting for input:

Code: Select all

#!/usr/bin/env python

import curses

screen = curses.initscr()
inp = ""
word = "quit"

for i in range(10000):
    # modify the screen
    screen.clear()
    screen.addstr("Type 'quit' to quit: (" + inp + ") " + "!" * (i % 10) +"\n")
    screen.refresh()

    # collect input if present or throw an error
    try:
        curses.halfdelay(1)
        inp += chr(screen.getch())
    except:
        pass

    # use the input in some way
    if inp == word:
        break
    if len(inp) > len(word):
        inp = ""

curses.endwin()


Continously scrolling text would take a bit more work but the idea is the same.

I think I get it now, but I might have to read through that a few more times

I'm awful at reading anyone else's code.

Thanks!

[Defience]

Here are a couple of things you can also play around with and maybe incorporate into what you're looking for:

Code: Select all


import time
while True:
    response = raw_input("Are you an elite hacker?  ")
    if response.lower() == "yes":
         print "Can you hack a myspace for me then?!"
         break
    elif response.lower() == "no":
        print "Poser! Do you know anyone that is?"
        break
    else:
        while True:
            print "Please enter a yes or no or I will keep asking the same question!"
            time.sleep(2)



Use ctrl + c to get that ^^ to stop running. Of course you could change the time or remove it all together.

Code: Select all


import time
response=raw_input("Are you ready?\n")
while (response.lower() != "yes"):
  if (response.lower() != "no"):
    time.sleep(2)
    response=raw_input("\nAre you ready?\n")
raw_input("let's get started!")