I am working on a Python class that is structured like the example in this answer: https://stackoverflow.com/a/1383744/576333. The class itself is keeping track of all created objects using a dictionary.
class Repository(object):
# All repositories are stored in this class-level dictionary such that
# all instances of this class maintain the same set.
all_repos = {}
def __init__(self, name, data):
"""
Create a repository object. If it has the required tags, include it in
the collection of all repositories.
"""
# Don't add it if it already exists
if not name in Repository.all_repos:
# Store the attributes
self.__dict__ = data
self.__dict__['name'] = name
Repository.all_repos.update({ name: self })
My question is what happens in python when I create a delete/remove method and want to purge an instance of Repository from the all_repos dictionary? Here is what I was planning on doing a method like that:
def remove(self):
repo = Repository.all_repos.pop(self.name) # pop it out
print "You just removed %s" % repo.name
With the following usage:
a= Repository('repo_name', {'attr1':'attr1_value',...}
a.remove()
At this point, a still exists, but not in Repository.all_repos. When will Python finally remove a?
I found this article to be very helpful to visualize garbage collection. It uses Ruby's GC for comparison, but it is well worth the read:
http://patshaughnessy.net/2013/10/24/visualizing-garbage-collection-in-ruby-and-python