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Declaring variables inside a switch statement [duplicate]
I saw a few answers to this issue, and I get it — you can't declare and assign variables inside a switch . But I'm wondering if the following is correct at throwing an error saying
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Why is it impossible to override a getter-only property and add a setter? [closed]
...nly property. It doesn't make sense for derivations to break this contract and make it read-write.
I'm with Microsoft on this one.
Let's say I'm a new programmer who has been told to code against the Baseclass derivation. i write something that assumes that Bar cannot be written to (since the Basec...
Struct inheritance in C++
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Other than what Alex and Evan have already stated, I would like to add that a C++ struct is not like a C struct.
In C++, a struct can have methods, inheritance, etc. just like a C++ class.
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Why does GCC generate 15-20% faster code if I optimize for size instead of speed?
I first noticed in 2009 that GCC (at least on my projects and on my machines) have the tendency to generate noticeably faster code if I optimize for size ( -Os ) instead of speed ( -O2 or -O3 ), and I have been wondering ever since why.
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Drawing a line/path on Google Maps
... mPaint.setColor(Color.RED);
mPaint.setStyle(Paint.Style.FILL_AND_STROKE);
mPaint.setStrokeJoin(Paint.Join.ROUND);
mPaint.setStrokeCap(Paint.Cap.ROUND);
mPaint.setStrokeWidth(2);
GeoPoint gP1 = new GeoPoint(19240000,-99120000);
GeoPoint gP2 = new...
Reminder - \r\n or \n\r?
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If you open a file in text mode (ie not binary) then the streams will convert the "\n" into the correct LTS for your platform. Then convert the LTS back to "\n" when you read the file.
As a result if you print "\r\n" to a windows file you will get the sequence "\r\r\n" in the physical file (ha...
What does a lazy val do?
...3
In contrast to a method (defined with def) a lazy val is executed once and then never again. This can be useful when an operation takes long time to complete and when it is not sure if it is later used.
scala> class X { val x = { Thread.sleep(2000); 15 } }
defined class X
scala> class Y ...
How to count the number of set bits in a 32-bit integer?
...ays addition'.
The 'best' algorithm really depends on which CPU you are on and what your usage pattern is.
Some CPUs have a single built-in instruction to do it and others have parallel instructions which act on bit vectors. The parallel instructions (like x86's popcnt, on CPUs where it's supported)...
What is 'Pattern Matching' in functional languages?
I'm reading about functional programming and I've noticed that Pattern Matching is mentioned in many articles as one of the core features of functional languages.
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Are negative array indexes allowed in C?
I was just reading some code and found that the person was using arr[-2] to access the 2nd element before the arr , like so:
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