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pythonpromptpython-interactive

Randomly change the prompt in the Python interpreter

It's kind of boring to always see the >>> prompt in Python. What would be the best way to go about randomly changing the prompt prefix?

I imagine an interaction like: 

This is a tobbaconist!>> import sys
Sorry?>> import math
Sorry?>> print sys.ps1
Sorry?
What?>>
Solution

  • According to the docs, if you assign a non-string object to sys.ps1 then it will evaluate the str function of it each time:

    If a non-string object is assigned to either variable, its str() is re-evaluated each time the interpreter prepares to read a new interactive command; this can be used to implement a dynamic prompt.

    Well now it's obvious, you should make it dynamic! Make an object with a __str__ method where you can place any logic you want:

    class Prompt:
    def __str__(self):
        # Logic to randomly determine string
        return string

    You can also make changes or insert things into this class as you go too. So for example, you could have a list of messages in Prompt that you append to, or change, and that will affect the console message.