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Is pass-by-value a reasonable default in C++11?
...by value into functions and methods is slow for large objects, and is generally frowned upon. Instead, C++ programmers tend to pass references around, which is faster, but which introduces all sorts of complicated questions around ownership and especially around memory management (in the event that ...
Is it better to return null or empty collection?
...llection might mean "0 items", returning Null could mean "no collection at all" - eg. if you are parsing HTML, looking for an <ul> with id="foo", <ul id="foo"></ul> could return empty collection; if there is no <ul> with id="foo" a null return would be better (unless you want...
Why no ICloneable?
...bad API now, since it does not specify whether the result is a deep or a shallow copy. I think this is why they do not improve this interface.
You can probably do a typed cloning extension method, but I think it would require a different name since extension methods have less priority than original...
CSV API for Java [closed]
Can anyone recommend a simple API that will allow me to use read a CSV input file, do some simple transformations, and then write it.
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SQLAlchemy: What's the difference between flush() and commit()?
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A Session object is basically an ongoing transaction of changes to a database (update, insert, delete). These operations aren't persisted to the database until they are committed (if your program aborts for some reason in mid-session transaction, any...
How to resolve “local edit, incoming delete upon update” message
...e svn st | grep ! | cut -f 7 -d' ' | xargs touch as one liner for touching all the missing files
– Tibor Blenessy
Dec 11 '13 at 16:31
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“new” keyword in Scala
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Is it when we try to instantiate java objects only?
Not at all. There is two general cases when you ommit new in scala.
With singleton objects (that are oftenly used to store static functions and as a kind of factory similar to what you may seen in java):
scala> object LonelyGuy ...
How to convert a scala.List to a java.util.List?
...n ClassNotFoundException: scala.collection.convert.Wrappers. Arrays.asList(foo : _*) works in this case.
– Mohan
Jun 27 '15 at 11:41
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Is it possible to get all arguments of a function as single object inside that function?
...t an "Object which has a length property of a non-negative Integer, and usually some indexed properties." From the mozilla link: "It is similar to an Array, but does not have any Array properties except length."
– Luke
Aug 7 '17 at 13:09
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How do you read a file into a list in Python? [duplicate]
...each line might have. When the with ends, the file will be closed automatically for you. This is true even if an exception is raised inside of it.
2. use of list comprehension
This could be considered inefficient as the file descriptor might not be closed immediately. Could be a potential issue wh...