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Which is more efficient, a for-each loop, or an iterator?
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If you are just wandering over the collection to read all of the values, then there is no difference between using an iterator or the new for loop syntax, as the new syntax just uses the iterator underwater.
If however, you mean by loop the old "c-style" loop:
for(int i=0; i&l...
Fragments within Fragments
I'm wondering if this is actually a bug in the Android API:
6 Answers
6
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How to find the size of localStorage
...ly developing a site that will make use of HTML5's localStorage. I've read all about the size limitations for different browsers. However, I haven't seen anything on how to find out the current size of a localStorage instance. This question seems to indicate that JavaScript doesn't have a built in...
What's the result of += in C and C++?
...7.1:
The assignment operator (=) and the compound assignment operators all group right-to-left. All require a modifiable
lvalue as their left operand and return an lvalue with the type and value of the left operand after the assignment has taken place.
EDIT : The behavior of (i+=10)+=10 in ...
Why are interface variables static and final by default?
...ariable. As for the part about final, that doesn't offer an explanation at all - it just describes what final means.
– pyrocrasty
May 9 '16 at 6:34
3
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Studies on optimal code width?
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Actually, the 80-column thing long precedes DOS. It comes from card punches, which were 80-column devices.
And to kind of answer the OP's question, one "study" has been going on for about 600 years now - the printed book. These ...
data.table vs dplyr: can one do something well the other can't or does poorly?
...j and by together is by design. By keeping related operations together, it allows to easily optimise operations for speed and more importantly memory usage, and also provide some powerful features, all while maintaining the consistency in syntax.
1. Speed
Quite a few benchmarks (though mostly on g...
Which Eclipse files belong under version control?
...ect-dir/.classpath
project-dir/.settings/*
should be in your SCM (especially .project and .classpath according to the Eclipse documentation).
The goal is that anyone can checkout/update his/her SCM workspace and import the Eclipse project into the Eclipse workspace.
For that, you want to use on...
Send and receive messages through NSNotificationCenter in Objective-C?
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@implementation TestClass
- (void) dealloc
{
// If you don't remove yourself as an observer, the Notification Center
// will continue to try and send notification objects to the deallocated
// object.
[[NSNotificationCenter defaultCenter] removeO...
Should I use Java's String.format() if performance is important?
We have to build Strings all the time for log output and so on. Over the JDK versions we have learned when to use StringBuffer (many appends, thread safe) and StringBuilder (many appends, non-thread-safe).
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