16.7. rlcompleter — Completion function for GNU readline

Source code: Lib/rlcompleter.py

The rlcompleter module defines a completion function suitable for the readline module by completing valid Python identifiers and keywords.

When this module is imported on a Unix platform with the readline module available, an instance of the Completer class is automatically created and its complete() method is set as the readline completer.

Example:

>>> import rlcompleter
>>> import readline
>>> readline.parse_and_bind("tab: complete")
>>> readline. <TAB PRESSED>
readline.__doc__          readline.get_line_buffer(  readline.read_init_file(
readline.__file__         readline.insert_text(      readline.set_completer(
readline.__name__         readline.parse_and_bind(
>>> readline.

The rlcompleter module is designed for use with Python’s interactive mode. A user can add the following lines to his or her initialization file (identified by the PYTHONSTARTUP environment variable) to get automatic Tab completion:

try:
    import readline
except ImportError:
    print("Module readline not available.")
else:
    import rlcompleter
    readline.parse_and_bind("tab: complete")

On platforms without readline, the Completer class defined by this module can still be used for custom purposes.