import re
class CEnum:
"""
Constructs a C style enum from a string argument, automatically
enumerating the provided labels (defaults to 0).
Example:
States = Enum("Off=-1, On=1, Ready, Busy")
will create the following values:
States.Off = -1
States.On = 1
States.Ready = 2
States.Busy = 3
In addition to tracking the values, the Enum class tracks the
order in which items where added.
"""
def __init__(self, value_list, separator=",", increment=True):
self.__enum_read_only = False
self.__enum_init_val = 0
self.__enum_order = list()
values = value_list.split(separator)
for val in values:
if re.search("[=:]",val):
(name,value) = re.split("\s*[=:]\s*",val)
if value:
self.__enum_init_val = int(value)
else:
name = val
self.__enum_order.append(name)
setattr(self,name,self.__enum_init_val)
if increment:
self.__enum_init_val += 1
else:
self.__enum_init_val -= 1
self.__enum_read_only = True
def __setattr__(self,name,value):
if not re.match("_CEnum",name):
if self.__enum_read_only:
raise AttributeError("Enum is Read-Only")
self.__dict__[name] = value
def __getattr__(self,name):
if name in self.__dict__.keys():
return name
raise AttributeError("No such attribute: " + name)
def __str__(self):
return self.__repr__()
def __repr__(self):
my_rep = "("
for val in self.__enum_order:
my_rep += val + "=" + str(self.__dict__[val])
if val != self.__enum_order[-1]:
my_rep += ","
my_rep = my_rep.rstrip() + ")"
return my_rep
def labels(self):
return list(self.__enum_order)
def count(self):
return len(self.__enum_order)
if __name__ == "__main__":
DaysOfWeek = CEnum("Sun=1,Mon,Tue,Wed,Thu,Fri,Sat")
print("DaysOfWeek.Sun = " + str(DaysOfWeek.Sun))
print("DaysOfWeek.Mon = " + str(DaysOfWeek.Mon))
print("DaysOfWeek.Tue = " + str(DaysOfWeek.Tue))
print("DaysOfWeek.Wed = " + str(DaysOfWeek.Wed))
print("DaysOfWeek.Thu = " + str(DaysOfWeek.Thu))
print("DaysOfWeek.Fri = " + str(DaysOfWeek.Fri))
print("DaysOfWeek.Sat = " + str(DaysOfWeek.Sat))
print("DaysOfWeek.Sun < DaysOfWeek.Sat ? " +
("True" if DaysOfWeek.Sun < DaysOfWeek.Sat else "False"))
print("DaysOfWeek.Sat < DaysOfWeek.Sun ? " +
("True" if DaysOfWeek.Sat < DaysOfWeek.Sun else "False"))
try:
DaysOfWeek.Sun = DaysOfWeek.Sat
print("DaysOfWeek.Sun = " + str(DaysOfWeek.Sun))
print("DaysOfWeek.Mon = " + str(DaysOfWeek.Mon))
print("DaysOfWeek.Tue = " + str(DaysOfWeek.Tue))
print("DaysOfWeek.Wed = " + str(DaysOfWeek.Wed))
print("DaysOfWeek.Thu = " + str(DaysOfWeek.Thu))
print("DaysOfWeek.Fri = " + str(DaysOfWeek.Fri))
print("DaysOfWeek.Sat = " + str(DaysOfWeek.Sat))
except AttributeError as ae:
print("Got exception: " + str(ae))
try:
DaysOfWeek.Bob = 27
print("DaysOfWeek.Bob = " + str(DaysOfWeek.Bob))
except AttributeError as ae:
print("Got exception: " + str(ae))
print("DaysOfWeek.count() = " + str(DaysOfWeek.count()))
print("DaysOfWeek.labels() = " + str(DaysOfWeek.labels()))
print(str(DaysOfWeek))
