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What are the “standard unambiguous date” formats for string-to-date conversion in R?
...' then '"%Y/%m/%d"' on the first non-'NA' element,
and give an error if neither works.
as.Date("01 Jan 2000") yields an error because the format isn't one of the two listed above. as.Date("01/01/2000") yields an incorrect answer because the date isn't in one of the two formats listed...
How to wait for several Futures?
...hing else.
The difference with for comprehension is that here you get the error of the first to fail, whereas with for comprehension you get the first error in traversal order of the input collection (even if another one failed first). For example:
val f1 = Future { Thread.sleep(1000) ; 5 / 0 }
va...
Why can't yield return appear inside a try block with a catch?
...at's kind of like saying you don't need exceptions because you can use the error code returning strategy commonly used in C so many years ago. I admit the technical difficulties may be significant, but this still severely limits the usefulness of yield, in my opinion, because of the spaghetti code y...
std::string formatting like sprintf
... ) + 1; // Extra space for '\0'
if( size <= 0 ){ throw std::runtime_error( "Error during formatting." ); }
std::unique_ptr<char[]> buf( new char[ size ] );
snprintf( buf.get(), size, format.c_str(), args ... );
return std::string( buf.get(), buf.get() + size - 1 ); // We do...
Scala downwards or decreasing for loop?
...the answer. I'm having trouble using this solution. Here is my stacktrace: Error:(57, 17) value class may not be a member of another class implicit class RichInt(val value: Int) extends AnyVal { ^
– robert
Dec 22 '15 at 20:40
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Correct way to use get_or_create?
...ng to use get_or_create for some fields in my forms, but I'm getting a 500 error when I try to do so.
5 Answers
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Command to escape a string in bash
...blems with ~. There are also portable sed one-liners stackoverflow.com/a/20053121/1073695
– Jo So
Oct 22 '15 at 1:49
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How to “EXPIRE” the “HSET” child key in redis?
I need to expire all keys in redis hash, which are older than 1 month.
11 Answers
11
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Why doesn't String switch statement support a null case?
...that is, String or a boxed primitive type or an enum type, then a run-time error will occur if the expression evaluates to null at run time. In the judgment of the designers of the Java programming language, this is a better outcome than silently skipping the entire switch statement or choosing to e...
Simulator or Emulator? What is the difference?
...a piece of software that mimics existing hardware/software, what should I call it? A simulator or an emulator?
21 Answers
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