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Why is subtracting these two times (in 1927) giving a strange result?
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It's a time zone change on December 31st in Shanghai.
See this page for details of 1927 in Shanghai. Basically at midnight at the end of 1927, the clocks went back 5 minutes and 52 seconds. So "1927-12-31 23:54:08" actually happened twic...
PHP - Merging two arrays into one array (also Remove Duplicates)
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As already mentioned, array_unique() could be used, but only when dealing with simple data. The objects are not so simple to handle.
When php tries to merge the arrays, it tries to compare the values of the array members. If a member is an ...
Mutable vs immutable objects
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Great response. One small question however: doesn't C++ have good support for immutability? Isn't the const-correctness feature sufficient?
– Dimitri C.
Sep 2 '10 at 7:13
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Using Build Flavors - Structuring source folders and build.gradle correctly
...src/main/java.
Do note that if you had 3 flavors and only wanted a custom one for flavor1, while flavor2 and flavor3 shared the same activity you could create a common source folders for those two other activities. You have total flexibility in creating new source folders and configuring the source...
What is the difference between Hibernate and Spring Data JPA
...nd it's intended for native querying, and if you only intend to use JDBC alone, then you are better off using Spring JDBC to deal with the JDBC verbosity.
Therefore, Hibernate and Spring Data are complementary rather than competitors.
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How to test that no exception is thrown?
I know that one way to do it would be:
15 Answers
15
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Regex to match only letters
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Use a character set: [a-zA-Z] matches one letter from A–Z in lowercase and uppercase. [a-zA-Z]+ matches one or more letters and ^[a-zA-Z]+$ matches only strings that consist of one or more letters only (^ and $ mark the begin and end of a string respectively).
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What is InputStream & Output Stream? Why and when do we use them?
Someone explain to me what InputStream and OutputStream are?
8 Answers
8
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Copy constructor for a class with unique_ptr
...) ) {}
};
int main()
{
A a( 42 );
A b = a;
}
You can, as NPE mentioned, use a move-ctor instead of a copy-ctor but that would result in different semantics of your class. A move-ctor would need to make the member as moveable explicitly via std::move:
A( A&& a ) : up_( std::move( a....
How to rollback just one step using rake db:migrate
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For starters
rake db:rollback will get you back one step
then
rake db:rollback STEP=n
Will roll you back n migrations where n is the number of recent migrations you want to rollback.
More references here.
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