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What is scope/named_scope in rails?
...a field to the Users Database (user.subscribed_to_newsletter = true). Naturally, you sometimes want to get those Users who are subscribed to your newsletter.
You could, of course, always do this:
User.where(subscribed_to_newsletter: true).each do #something
Instead of always writing this you cou...
Debug vs. Release performance
...
Partially true. In debug mode, the compiler emits debug symbols for all variables and compiles the code as is. In release mode, some optimizations are included:
unused variables do not get compiled at all
some loop variables are ...
Prevent unit tests but allow integration tests in Maven
...out skipping failsafe tests.
Property value seems to magically default to false -->
<skipTests>${skip.surefire.tests}</skipTests>
</configuration>
</plugin>
This allows you to run mvn verify -Dskip.surefire.tests and only surefire, not failsa...
Database Structure for Tree Data Structure
... using the employee ID to link an employee to their supervisor. This is usually a sub-optimal approach. An approach that often works better is to model the org structure separate from employees themselves, and maintain the employee as an attribute of the structure. This way, when an employee leaves ...
Heroku/GoDaddy: send naked domain to www [closed]
... at the bottom of the "Domain Information" section:
If you do this then all traffic to yourdomain.com will be routed to the Heroku app CNAME (which is the better approach).
One note, however, if you are on the Cedar stack then don't use proxy.heroku.com for the host of your www CNAME. Instead us...
What's the best practice for putting multiple projects in a git repository? [closed]
...olution 1
A single repository can contain multiple independent branches, called orphan branches. Orphan branches are completely separate from each other; they do not share histories.
git checkout --orphan BRANCHNAME
This creates a new branch, unrelated to your current branch. Each project should...
How to color the Git console?
...obal color.ui auto
The color.ui is a meta configuration that includes all the various color.* configurations available with git commands. This is explained in-depth in git help config.
So basically it's easier and more future proof than setting the different color.* settings separately.
In-d...
Where is virtualenvwrapper.sh after pip install?
I'm trying to setup virtualenvwrapper on OSX, and all the instructions and tutorials I've found tell me to add a source command to .profile, pointing towards virtualenvwrapper.sh. I've checked all the python and site-packages directories, and I can't find any virtualenvwrapper.sh. Is this something ...
Should I use scipy.pi, numpy.pi, or math.pi?
...gt;> math.pi == np.pi == scipy.pi
True
So it doesn't matter, they are all the same value.
The only reason all three modules provide a pi value is so if you are using just one of the three modules, you can conveniently have access to pi without having to import another module. They're not provi...
What is Virtual DOM?
Recently, I looked at Facebook's React framework. It uses a concept called "the Virtual DOM," which I didn't really understand.
...