def traceParseAction(f):
    f = _trim_arity(f)
    def z(*paArgs):
        thisFunc = f.__name__
        s,l,t = paArgs[-3:]
        if len(paArgs)>3:
            thisFunc = paArgs[0].__class__.__name__ + '.' + thisFunc
        sys.stderr.write( ">>entering %s(line: '%s', %d, %r)\n" % (thisFunc,line(l,s),l,t) )
        try:
            ret = f(*paArgs)
        except Exception as exc:
            sys.stderr.write( "<<leaving %s (exception: %s)\n" % (thisFunc,exc) )
            raise
        sys.stderr.write( "<<leaving %s (ret: %r)\n" % (thisFunc,ret) )
        return ret
    try:
        z.__name__ = f.__name__
    except AttributeError:
        pass
    return z