Access python interpreter history

A quick note to myself about accessing the commands from history while working in Python interpreter.

• readline module provides the necessary methods to access the history in runtime.
  • See get_current_history_length and get_history_item
• Commands run inside the interpreter are saved by default at .python_history in the user’s home directory

For convenience, I have added a short helper to my python startup file, so it is always available during interactive sessions.

import readline

def show_history(num_recent=10):
    """ Show the entries from interpreter history buffer

    Args:
        num_recent (int): Number of entries to show (default:10)
    """
    history_length = readline.get_current_history_length()
    # Index of the underlying history buffer one based
    # https://docs.python.org/3/library/readline.html?highlight=readline#readline.get_history_item
    start = max(1, history_length - num_recent)
    for i in range(start, history_length):
        print("{} {}".format(i, readline.get_history_item(i)))