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Clang vs GCC for my Linux Development project

...Clang's extremely clear diagnostics are definitely easier for beginners to interpret. Consider this simple snippet: #include <string> #include <iostream> struct Student { std::string surname; std::string givenname; } std::ostream& operator<<(std::ostream& out, Student c...
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How to get month name from Calendar

Is there a oneliner to get the name of the month when we know int monthNumber = calendar.get(Calendar.MONTH) ? Or what is the easiest way? ...
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Reshaping data.frame from wide to long format

I have some trouble to convert my data.frame from a wide table to a long table. At the moment it looks like this: 9 Answe...
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Hibernate: hbm2ddl.auto=update in production?

...l, such as pushing the length of a String column up over 255 and seeing it convert to text, mediumtext, etc etc. Granted, I don't think there is really a way to "convert datatypes" with without creating a new column, copying the data and blowing away the old column. But the minute your database ha...
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Difference between class and type

... A class is a type. An interface is a type. A primitive is a type. An array is a type. Therefore, every type is also either a class (including an enum constant), an interface, a primitive, or an array. There are two distinct categories of types:...
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Why does C++ not allow inherited friendship?

...n? Was friendship really just a limited hack that has since found its way into a few obscure respectable uses? 10 Answers ...
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What is more efficient? Using pow to square or just multiply it with itself?

...T(2, b*b) TEST(3, b*b*b) TEST(4, b*b*b*b) TEST(5, b*b*b*b*b) template <int exponent> double testpow(double base, long loops) { double x = 0.0; boost::posix_time::ptime startTime = now(); for (long i=0; i<loops; ++i) { x += std::pow(base, exponent); x += std...
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HashSet vs. List performance

...yed as a graph: Here's the code: static void Main(string[] args) { int times = 10000000; for (int listSize = 1; listSize < 10; listSize++) { List<string> list = new List<string>(); HashSet<string> hashset = new HashSet<string>(); ...
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How to create composite primary key in SQL Server 2008

... create table my_table ( column_a integer not null, column_b integer not null, column_c varchar(50), primary key (column_a, column_b) ); share | ...
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Difference between case object and object

... Point 3 and 4 of this answer is correct difference between case objects and objects. Point 1 and 2 doesn't matter for singleton objects. And singleton objects are always Products with arity 0 so point 5 doesn't matter also. ...