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What does @synchronized() do as a singleton method in objective C?
...probably isn't multithreaded, and you probably don't need to use it (especially if the singleton itself isn't thread-safe).
Edit: Adding some more information that wasn't in the original answer from 2011.
The @synchronized directive prevents multiple threads from entering any region of code that...
Database design for audit logging
...a of what the old record looked like.
So for example, if you had a table called Opportunities to track sales deals, you would actually create two separate tables:
Opportunities
Opportunities_Content (or something like that)
The Opportunities table would have information you'd use to uniquely iden...
Sorting related items in a Django template
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I added an alternate solution for you. It should allow you the flexibility you need.
– tawmas
Jun 30 '11 at 22:39
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Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
...rough for i up to n, doing two things: pressing A once and pressing select all + copy followed by paste j times (actually j-i-1 below; note the trick here: the contents are still in the clipboard, so we can paste it multiple times without copying each time). We only have to consider up to 4 consecut...
difference between scope and namespace of ruby-on-rails 3 routing
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from the rails guide
"The namespace scope will automatically add :as as well as :module and :path prefixes."
so
namespace "admin" do
resources :contexts
end
is the same as
scope "/admin", as: "admin", module: "admin" do
resources :contexts
end
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Using IoC for Unit Testing
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Generally speaking, a DI Container should not be necessary for unit testing because unit testing is all about separating responsibilities.
Consider a class that uses Constructor Injection
public MyClass(IMyDependency dep) { }
...
How to vertically align into the center of the content of a div with defined width/height?
What would be the correct method to vertically center any content in a defined width/height div .
4 Answers
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Count number of matches of a regex in Javascript
... mentioned in my earlier answer, you can use RegExp.exec() to iterate over all matches and count each occurrence; the advantage is limited to memory only, because on the whole it's about 20% slower than using String.match().
var re = /\s/g,
count = 0;
while (re.exec(text) !== null) {
++count;
...
What is the difference between min SDK version/target SDK version vs. compile SDK version?
...e earliest release of the Android SDK that your application can run on. Usually this is because of a problem with the earlier APIs, lacking functionality, or some other behavioural issue.
The target sdk version is the version your application was targeted to run on. Ideally, this is because of some...
How do I byte-compile everything in my .emacs.d directory?
...rt of provides better defaults and some nice customizations to default install of Emacs.
6 Answers
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