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Error “initializer element is not constant” when trying to initialize variable with const
...over, in C language, the term "constant" refers to literal constants (like 1, 'a', 0xFF and so on), enum members, and results of such operators as sizeof. Const-qualified objects (of any type) are not constants in C language terminology. They cannot be used in initializers of objects with static sto...
SQL Add foreign key to existing column
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191
Error indicates that there is no UserID column in your Employees table. Try adding the column ...
Boolean operators && and ||
...an return a vector, like this:
((-2:2) >= 0) & ((-2:2) <= 0)
# [1] FALSE FALSE TRUE FALSE FALSE
The longer form evaluates left to right examining only the first element of each vector, so the above gives
((-2:2) >= 0) && ((-2:2) <= 0)
# [1] FALSE
As the help page says...
How does HashSet compare elements for equality?
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138
It uses an IEqualityComparer<T> (EqualityComparer<T>.Default unless you specify a ...
Sleep Command in T-SQL?
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Look at the WAITFOR command.
E.g.
-- wait for 1 minute
WAITFOR DELAY '00:01'
-- wait for 1 second
WAITFOR DELAY '00:00:01'
This command allows you a high degree of precision but is only accurate within 10ms - 16ms on a typical machine as it relies on GetTickCount. So,...
Get TransactionScope to work with async / await
...nContext based on this example http://blogs.msdn.com/b/pfxteam/archive/2012/01/20/10259049.aspx .
3 Answers
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Lambda function in list comprehensions
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271
The first one creates a single lambda function and calls it ten times.
The second one doesn't ca...
count number of lines in terminal output
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491
Pipe the result to wc using the -l (line count) switch:
grep -Rl "curl" ./ | wc -l
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NULL vs nil in Objective-C
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edited Mar 24 '13 at 15:23
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How to suppress warnings globally in an R Script
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You could use
options(warn=-1)
But note that turning off warning messages globally might not be a good idea.
To turn warnings back on, use
options(warn=0)
(or whatever your default is for warn, see this answer)
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