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@nsfyn55
nsfyn55 / contravariance.scala
Last active Oct 13, 2015
Contravariance Example
View contravariance.scala
/*
Invariant:
String is subclass of Object but in java
List<String> is not a subclass of List<Object>
Covariant
String in scala is a subclass of Object
List[String] is a subclass of List[Object]
View Yipit Cache Machine
from django.db import models
from caching.base import CachingMixing, CachingManager, CachingQuerySet
class OurModel(CachingMixin, models.Model):
data = models.IntegerField()
objects = CachedManager(default_from_cache=True, cache_timeout=1200)
View gist:1439534
from django.db import models
from caching.base import CachingManager, CachingMixin
class CacheIt(CachingMixin, models.Model):
key_data = models.CharField(max_length=30)
related_stuff = models.ForeignKey('related.RelatedStuff')
objects = CachingManager()