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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...
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...
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 do I generate random number for each row in a TSQL Select?
...1.8b row table every day, so it was happening about once a week! Fix is to cast the checksum to bigint before the abs.
– EvilPuppetMaster
Jan 29 '16 at 1:11
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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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