toplevel.py 文件源码

def tracing(f):
    """Enable tracing just within a function call."""
    def globaltrace(frame,why,arg):
        if why == "call": return localtrace
        return None
    def localtrace(frame, why, arg):
        if why == "line":
            fname = frame.f_code.co_filename
            lineno = frame.f_lineno
            base = os.path.basename(fname)
            print("%s(%s): %s" % (base, lineno,
                                  linecache.getline(fname, lineno)))
        return localtrace
    @wrap(f)
    def wrapper(*args,**kw):
        sys.settrace(globaltrace)
        result = f(*args,**kw)
        sys.settrace(None)
        return result
    return wrapper