Cookbook: Ignoring some commands in history

This hack emulates the HISTIGNORE functionality in bash. It only hides relevant commands in the readline UI, not the internal history file. To use, run it at startup via c.InteractiveShellApp.exec_files in your ipython_config.py

# our history_ignore predicate
history_ignore = lambda str: str.startswith("cd")

# hijack the readline.add_history method
get_ipython().readline.old_add_history = get_ipython().readline.add_history
def my_add_history(str):
    if not history_ignore(str):
        get_ipython().readline.old_add_history(str)

get_ipython().readline.add_history = my_add_history

#Force a readline history reload, forcing it to go through our hacked method
#WARNING: this relies on the internals of ipython refilling the history with "refill_readline_hist"
#This is up to date Oct 2011, but may change in the future.
get_ipython().readline.clear_history()
get_ipython().refill_readline_hist()