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Java Generics: Cannot cast List to List? [duplicate]
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If you do have to cast from List<DataNode> to List<Tree>, and you know it is safe to do so, then an ugly way to achieve this is to do a double-cast:
List<DataNode> a1 = new ArrayList<DataNode>();
List<Tree> b1 =...
Why does this code segfault on 64-bit architecture but work fine on 32-bit?
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The cast to int* masks the fact that without the proper #include the return type of malloc is assumed to be int. IA-64 happens to have sizeof(int) < sizeof(int*) which makes this problem obvious.
(Note also that because of t...
How can I select the first day of a month in SQL?
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The casting of a string (i.e. "5/1/2009") to datetime is certainly more legible but we found code a while back that would return the first of the month...
DECLARE @Date DATETIME
//...
SELECT DATEADD(mm, DATEDIFF(mm,0,@Date), 0)
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Elegant solution to duplicate, const and non-const, getters? [duplicate]
...e C++ books that the way to do it is to implement the non-const version by casting away the const from the other function.
It's not particularly pretty, but it is safe. Since the member function calling it is non-const, the object itself is non-const, and casting away the const is allowed.
class F...
Does the 'mutable' keyword have any purpose other than allowing the variable to be modified by a con
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Without the mutable keyword you will eventually be forced to use const_cast to handle the various useful special cases it allows (caching, ref counting, debug data, etc.). Unfortunately const_cast is significantly more destructive than mutable because it forces the API client to destroy the cons...
How to convert a number to string and vice versa in C++
...ingstream with std::ostrstream. The latter is deprecated
Use boost lexical cast. If you are not familiar with boost, it is a good idea to start with a small library like this lexical_cast. To download and install boost and its documentation go here. Although boost isn't in C++ standard many librarie...
Type Checking: typeof, GetType, or is?
...type at execution time. There are rarely any cases to use is as it does a cast and, in most cases, you end up casting the variable anyway.
There is a fourth option that you haven't considered (especially if you are going to cast an object to the type you find as well); that is to use as.
Foo foo ...
How to convert from System.Enum to base integer?
...g any System.Enum derived type to its corresponding integer value, without casting and preferably without parsing a string.
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Select n random rows from SQL Server table
...sOrderDetail table:
SELECT * FROM Sales.SalesOrderDetail
WHERE 0.01 >= CAST(CHECKSUM(NEWID(),SalesOrderID) & 0x7fffffff AS float)
/ CAST (0x7fffffff AS int)
The SalesOrderID column is included in
the CHECKSUM expression so that
NEWID() evaluates once per row to
achi...
How to combine date from one field with time from another field - MS SQL Server
...oduced in SQL Server 2008. If you insist on adding, you can use Combined = CAST(MyDate AS DATETIME) + CAST(MyTime AS DATETIME)
Edit2 regarding loss of precision in SQL Server 2008 and up (kudos to Martin Smith)
Have a look at How to combine date and time to datetime2 in SQL Server? to prevent los...