import scrib_util as util

# Clones list/set/dict structures recursively; otherwise returns identity

def clone_collection(c):

if c is None:

return None

if isinstance(c, list):

return clone_list_aux(c)

elif isinstance(c, set):

return clone_set_aux(c)

elif isinstance(c, dict):

return clone_dict_aux(c)

else:

return c

# Could make the following non-public

def clone_list_aux(list_):

if list_ is None:

return None

if not isinstance(list_, list):

util.report_error("Expected list, not: " + list)

clone = []

for x in list_:

clone.append(clone_collection(x))

return clone

def clone_set_aux(set_):

if set_ is None:

return None

if not isinstance(set_, set):

util.report_error("Expected set, not: " + set)

clone = set([])

for x in set_:

clone.add(clone_collection(x))

return clone

def clone_dict_aux(dict_):

if dict_ is None:

return None

if not isinstance(dict_, dict):

util.report_error("Expected dict, not: " + type(dict_))

clone = {}

for k in dict_.keys():

clone[clone_collection(k)] = clone_collection(dict_[k])

return clone