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Remove ActiveRecord in Rails 3
Now that Rails 3 beta is out, I thought I'd have a look at rewriting an app I have just started work on in Rails 3 beta, both to get a feel for it and get a bit of a head-start. The app uses MongoDB and MongoMapper for all of its models and therefore has no need for ActiveRecord. In the previous ver...
Git's famous “ERROR: Permission to .git denied to user”
...
This was it. You saved me a huge headache. Now I just have to remember to run ssh-add ... every time I want to switch my github/ssh logins.
– Cerin
Nov 4 '12 at 5:08
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Use 'class' or 'typename' for template parameters? [duplicate]
...particularly clear, to be honest. in T::A *obj; the language, as far as I know, should parse the statement as a declaration because of the declaration rule: anything that looks like a declaration, even if it ambiguously looks like something else, should resolve into a declaration[0]. I also didn't f...
How to avoid reinstalling packages when building Docker image for Python projects?
...c66c7
As you can see above, this time docker uses cache during the build. Now, let's update requirements.txt:
# requirements.txt
pytest==2.3.4
ipython
Below is the output of docker build:
Sending build context to Docker daemon 5.12 kB
Sending build context to Docker daemon
Step 0 : FROM dockerf...
Mimicking sets in JavaScript?
...or somethings called ES 2015 has a built-in Set object. It is implemented now in some browsers. Since browser availability changes over time, you can look at the line for Set in this ES6 compatibility table to see the current status for browser availability.
One advantage of the built-in Set objec...
How to use Class in Java?
... what they really do behind the scenes over at this question , so we all know that Vector<int[]> is a vector of integer arrays, and HashTable<String, Person> is a table of whose keys are strings and values Person s.
However, what stumps me is the usage of Class<> .
...
How to get current time and date in Android
...an (but no longer should - see below!) use android.text.format.Time:
Time now = new Time();
now.setToNow();
From the reference linked above:
The Time class is a faster replacement
for the java.util.Calendar and
java.util.GregorianCalendar classes.
An instance of the Time class
represe...
What is scope/named_scope in rails?
...a collection. Sounds complicated? It isn't. Imagine this:
You have Users. Now, some of those Users are subscribed to your newsletter. You marked those who receive a newsletter by adding a field to the Users Database (user.subscribed_to_newsletter = true). Naturally, you sometimes want to get those ...
What is an intuitive explanation of the Expectation Maximization technique? [closed]
...e could find the exact means if we wanted).
This is, generally speaking, known as maximum likelihood estimation. Given some data, we compute the value of a parameter (or parameters) that best explains that data.
Now imagine that we cannot see which value was sampled from which group. Everything lo...
How to implement a ConfigurationSection with a ConfigurationElementCollection
...se "add" the default one but i changed it just for the sake of this post.
Now all of our nested Elements have been implemented now we should aggregate all of those in a class which has to implement System.Configuration.ConfigurationSection
CustomApplicationConfigSection
public class CustomApplica...