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“unary operator expected” error in Bash if condition
... you don't need to use two "[", which amounts to two processes ("[" is actually a program) instead of one.
It goes by this syntax: ${VARIABLE:-default}.
The whole thing has to be thought in such a way that this "default" value is something distinct from a "valid" value/content.
If that's not poss...
Iterate through a C++ Vector using a 'for' loop
...++ language. I have been starting to use vectors, and have noticed that in all of the code I see to iterate though a vector via indices, the first parameter of the for loop is always something based on the vector. In Java I might do something like this with an ArrayList:
...
Bash script - variable content as a command to run
...eries.txt | wc -l)
$(perl test.pl test2 $count)
However, if you want to call your Perl command later, and that's why you want to assign it to a variable, then:
#!/bin/bash
count=$(cat last_queries.txt | wc -l)
var="perl test.pl test2 $count" # You need double quotes to get your $count value subst...
Help with C# generics error - “The type 'T' must be a non-nullable value type”
...nt required by Nullable<T> itself. In other words, you could try to call:
CoalesceMax<string>(...)
which wouldn't make sense, as Nullable<string> isn't valid.
share
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WPF Data Binding and Validation Rules Best Practices
I have a very simple WPF application in which I am using data binding to allow editing of some custom CLR objects. I am now wanting to put some input validation in when the user clicks save. However, all the WPF books I have read don't really devote any space to this issue. I see that you can create...
When should I use cross apply over inner join?
...r
),
t AS
(
SELECT 1 AS id
UNION ALL
SELECT 2
)
SELECT *
FROM t
JOIN q
ON q.rn <= t.id
runs for almost 30 seconds, while this one:
WITH t AS
(
SELECT 1 AS id
UNION ALL
SELECT 2
...
Eclipse debugger always blocks on ThreadPoolExecutor without any obvious exception, why?
...s that a RuntimeException was encountered in a Daemon thread. This is typically uncaught at runtime, unless the original developer caught and handled the exception.
Typically, the debugger in Eclipse is configured to suspend execution at the location where the exception was thrown, on all uncaught ...
@Transactional(propagation=Propagation.REQUIRED)
... such logical transaction scope can determine rollback-only status individually, with an outer transaction scope being logically independent from the inner transaction scope. Of course, in case of standard PROPAGATION_REQUIRED behavior, all these scopes will be mapped to the same physical transactio...
How do I force detach Screen from another SSH session?
...creen session still thinks it's attached. Maybe it is. Perhaps I don't really know what that means.
4 Answers
...
How to use RestSharp with async/await
...g to has been made by me :) So let me show you how to use it, as it is actually very simple. Previously you had methods like ExecuteAsyncGet that would return a RestSharp custom type named RestRequestAsyncHandle. This type could not be awaited as async/await works on Task and Task<T> return ty...