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What is the best way to concatenate two vectors?
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What's a concise way to check that environment variables are set in a Unix shell script?
...he Bourne Shell (1978 or thereabouts). The ${var:?} construct is slightly more recent: I think it was in System III UNIX circa 1981, but it may have been in PWB UNIX before that. It is therefore in the Korn Shell, and in the POSIX shells, including specifically Bash.
It is usually documented in th...
Getting unique items from a list [duplicate]
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Is this faster/more efficient than a HashSet<T>? I don't think so. Not bothering to downvote, though :-)
– Vinay Sajip
Sep 7 '09 at 9:21
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Why and not taking font-family and font-size from body?
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I agree, that approach is more practical. I just wanted to demonstrate the behavior you were seeing by using the inherit approach.
– spoulson
May 20 '10 at 17:04
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Undefined, unspecified and implementation-defined behavior
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Difference between pre-increment and post-increment in a loop?
...ss the post-increment operator is definitely what's required.
There's some more discussion here.
In C++ if you're using STL, then you may be using for loops with iterators. These mainly have overridden ++ operators, so sticking to pre-increment is a good idea. Compilers get smarter all the time thou...
find() with nil when there are no records
...method. In that case the only extra line you need is the rescue line. Much more elegant and easier to handle than checking for nil with an if statement.
– morgler
Aug 1 '17 at 7:30
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Spring Boot - inject map from application.yml
..., controlling how missing properties are handled, etc. See the javadoc for more information.
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SQL parser library for Java [closed]
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