support __line__ vriable.

lineon.py

# -*- coding: utf-8 -*-

__doc__ = """
usage:
    python lineon.py somefile.py

or

# write your top of source.
lineon.apply(sys) 
""""

def trace(frame, event, arg):
    """fuck a line event and set global variale"""
    if event == 'line':
        frame.f_globals['__line__'] = frame.f_lineno
    return trace

def apply(module):
    """add trace func to module"""
    if hasattr(module, 'settrace'):
        module.settrace(trace)
    
if __name__ == '__main__':
    import sys

    args = sys.argv[1:]
    if len(args) == 1 and args[0].endswith('.py'):
        apply(sys)
        execfile(args[0])