snippets for export PYTHONSTARTUP=~/.pythonrc

.pythonrc

# This is the actual file that combines all of the other snippets
# I've been using it for a while, so it's officially Bug Free (TM)

# Python startup script.            vim: set ft=python :
# from http://www.norvig.com/python-iaq.html
# also see Tarek Ziade's _Expert_Pythom_Programming_ page 19
import os, sys

# Coloured prompt
if os.getenv('TERM') in ('xterm', 'vt100', 'rxvt', 'Eterm', 'putty'):
    try:
        import readline
    except ImportError:
        sys.ps1 = '\033[0;32m>>> \033[0m'
        sys.ps2 = '\033[0;32m... \033[0m'
    else:
        sys.ps1 = '\001\033[0;32m\002>>> \001\033[0m\002'
        sys.ps2 = '\001\033[0;32m\002... \001\033[0m\002'

# Completion!
try:
    import readline
except ImportError:
    print("Module readline not available.")
else:
    # persistent history
    histfile = os.path.expanduser('~/.pythonhistory')
    try:
        readline.read_history_file(histfile)
    except IOError:
        pass
    import atexit
    atexit.register(readline.write_history_file, histfile)
    del histfile, atexit
    # tab completion
    try:
        sys.path.append(os.path.join(os.getenv('HOME'), 'src', 'rlcompleter2'))
        import rlcompleter2
        rlcompleter2.setup()
        del rlcompleter2
    except ImportError:
        import rlcompleter
        readline.parse_and_bind("tab: complete")
        del rlcompleter
    del readline

del sys
del os

pythonrc-coloured-prompt

# Coloured prompt
import os, sys
if os.getenv('TERM') in ('xterm', 'vt100', 'rxvt', 'Eterm', 'putty'):
    try:
        import readline
    except ImportError:
        sys.ps1 = '\033[0;32m>>> \033[0m'
        sys.ps2 = '\033[0;32m... \033[0m'
    else:
        sys.ps1 = '\001\033[0;32m\002>>> \001\033[0m\002'
        sys.ps2 = '\001\033[0;32m\002... \001\033[0m\002'
        del readline
del os, sys

pythonrc-history-snippet

# Persistent history
try:
    import readline
except ImportError:
    print("Module readline not available.")
else:
    import os
    histfile = os.path.expanduser('~/.pythonhistory')
    try:
        readline.read_history_file(histfile)
    except IOError:
        pass
    import atexit
    atexit.register(readline.write_history_file, histfile)
    del histfile, atexit, readline, os

pythonrc-tab-completion

# Tab-completion
try:
    import readline
except ImportError:
    print("Module readline not available.")
else:
    import os, sys
    try:
        # look for rlcompleter2 in ~/src, it's a bit more advanced
        sys.path.append(os.path.expanduser('~/src/rlcompleter2'))
        import rlcompleter2
        rlcompleter2.setup()
        del rlcompleter2
    except ImportError:
        # fall back to rlcompleter from the standard library
        import rlcompleter
        readline.parse_and_bind("tab: complete")
        del rlcompleter
    del readline, os, sys

Moved to https://github.com/mgedmin/dotfiles/blob/master/python
see also https://github.com/mgedmin/dotfiles/blob/master/bashrc.python

I'm currently making a script/package to enforce XDG standards. Is it alright if I yank'n'paste your script (removing the coloured prompt) into it?

I'm not sure what my Python REPL tweaks have to do with XDG standards, but feel free. It's not really my code anyway, I've seen bits and pieces on the Internet and assembled them.

Thanks. I arrived here when looking at how to change the histfile, which was what I wanted.

I've tweaked it a bit :)

I am kind of curious: why do we import rlcompleter when, per documentation, importing readline already enables tab completion? Is it a version thing?

readline enables command-line editing and provides a hook for custom tab-completion. rlcompleter implements a readline tab-completion hook that can understand and complete Python code. rlcompleter2 was a slightly more advanced version, but seems unmaintained these days (last release in 2010).