PyBitmessage-2021-04-27/src/singleton.py

23 lines
520 B
Python

"""
Singleton decorator definition
"""
from functools import wraps
def Singleton(cls):
"""
Decorator implementing the singleton pattern:
it restricts the instantiation of a class to one "single" instance.
"""
instances = {}
# https://github.com/sphinx-doc/sphinx/issues/3783
@wraps(cls)
def getinstance():
"""Find an instance or save newly created one"""
if cls not in instances:
instances[cls] = cls()
return instances[cls]
return getinstance