reload.py 文件源码

def updateFunction(old, new, debug, depth=0, visited=None):
    #if debug and depth > 0:
        #print "    -> also updating previous version", old, " -> ", new

    old.__code__ = new.__code__
    old.__defaults__ = new.__defaults__

    if visited is None:
        visited = []
    if old in visited:
        return
    visited.append(old)

    ## finally, update any previous versions still hanging around..
    if hasattr(old, '__previous_reload_version__'):
        maxDepth = updateFunction(old.__previous_reload_version__, new, debug, depth=depth+1, visited=visited)
    else:
        maxDepth = depth

    ## We need to keep a pointer to the previous version so we remember to update BOTH
    ## when the next reload comes around.
    if depth == 0:
        new.__previous_reload_version__ = old
    return maxDepth



## For classes:
##  1) find all instances of the old class and set instance.__class__ to the new class
##  2) update all old class methods to use code from the new class methods