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Difference between object and class in Scala
I'm just going over some Scala tutorials on the Internet and have noticed in some examples an object is declared at the start of the example.
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Any reason not to use '+' to concatenate two strings?
A common antipattern in Python is to concatenate a sequence of strings using + in a loop. This is bad because the Python interpreter has to create a new string object for each iteration, and it ends up taking quadratic time. (Recent versions of CPython can apparently optimize this in some cases, b...
“cannot resolve symbol R” in Android Studio
In every instance in all of my classes where I reference R.id.something , the R is in red and it says "cannot resolve symbol R". Also every time there is R.layout.something it is underlined in red and says "cannot resolve method setContentView(?)". The project always builds fine. It is annoyin...
What is the difference between char array and char pointer in C?
I am trying to understand pointers in C but I am currently confused with the following:
8 Answers
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Identifying and removing null characters in UNIX
I have a text file containing unwanted null characters (ASCII NUL, \0 ). When I try to view it in vi I see ^@ symbols, interleaved in normal text. How can I:
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Java: Multiple class declarations in one file
In Java, you can define multiple top level classes in a single file, providing that at most one of these is public (see JLS §7.6 ). See below for example.
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Access an arbitrary element in a dictionary in Python
...vely and iteratively:
mydict.itervalues().next()
If you want it to work in both Python 2 and 3, you can use the six package:
six.next(six.itervalues(mydict))
though at this point it is quite cryptic and I'd rather prefer your code.
If you want to remove any item, do:
key, value = mydict.popi...
How to compare only date components from DateTime in EF?
I am having two date values, one already stored in the database and the other selected by the user using DatePicker. The use case is to search for a particular date from the database.
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Improving bulk insert performance in Entity framework [duplicate]
I want to insert 20000 records in a table by entity framework and it takes about 2 min. Is there any way other than using SP to improve its performance. This is my code:
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What is an undefined reference/unresolved external symbol error and how do I fix it?
What are undefined reference/unresolved external symbol errors? What are common causes and how to fix/prevent them?
34 Answ...