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When should we use Observer and Observable?
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You have a concrete example of a Student and a MessageBoard. The Student registers by adding itself to the list of Observers that want to be notified when a new Message is posted to the MessageBoard. When a Message is added to the MessageBoard, it iterates over it...
Compile, Build or Archive problems with Xcode 4 (and dependencies)
...ed over the past several weeks to cover more general issues with xcode4 (and upgrading projects form older xcode s).
14 ...
What is the difference between range and xrange functions in Python 2.X?
Apparently xrange is faster but I have no idea why it's faster (and no proof besides the anecdotal so far that it is faster) or what besides that is different about
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Difference between rake db:migrate db:reset and db:schema:load
The difference between rake db:migrate and rake db:reset is pretty clear in my head. The thing which I don't understand is how rake db:schema:load different from the former two.
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How to Store Historical Data
Some co-workers and I got into a debate on the best way to store historical data. Currently, for some systems, I use a separate table to store historical data, and I keep an original table for the current, active record. So, let's say I have table FOO. Under my system, all active records will go ...
Array or List in Java. Which is faster?
I have to keep thousands of strings in memory to be accessed serially in Java. Should I store them in an array or should I use some kind of List ?
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Difference between a User and a Login in SQL Server
...ly don't mess with. One of them that has me confused is the area of Logins and Users. Seems like it should be a pretty simple topic...
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Can't update Macports (with Mac OS X Mavericks)
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Install the "Command Line Tools" first:
sudo xcode-select --install
(Explicitly agreeing to the license is sometimes necessary via "sudo xcodebuild -license")
Then upgrade the ports:
sudo port -v selfupdate
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Why is it necessary to set the prototype constructor?
....create(Person.prototype);
Now what happens when we create a new Student and copy it?
var student1 = new Student("trinth");
console.log(student1.copy() instanceof Student); // => false
The copy is not an instance of Student. This is because (without explicit checks), we'd have no wa...
How to lock compiled Java classes to prevent decompilation?
... also scramble your code flow in a way that makes it really hard to follow and works as an excellent code optimizer...
Also many of the obfuscators are also able to scramble your string constants and remove unused code.
Another possible solution (not necessarily excluding the obfuscation) is to us...