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Enumerable.Empty() equivalent for IQueryable
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@Nauman - you actually create an [empty] T array - no new object of T is actually created.
– zastrowm
Feb 20 '14 at 15:56
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PostgreSQL return result set as JSON array?
...up
The json_agg function produces this result out of the box. It automatically figures out how to convert its input into JSON and aggregates it into an array.
SELECT json_agg(t) FROM t
There is no jsonb (introduced in 9.4) version of json_agg. You can either aggregate the rows into an array and ...
Casting a variable using a Type variable
...th a value of 1000, the compiler
// doesn't know the exact type so it will allow you to call any
// property or method on it, but will crash if it doesn't exist
dynamic value3 = Convert.ChangeType(value1, intType);
I've written the answer with generics, because I think it is a very likely sign of ...
Best way to specify whitespace in a String.Split operation
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If you just call:
string[] ssize = myStr.Split(null); //Or myStr.Split()
or:
string[] ssize = myStr.Split(new char[0]);
then white-space is assumed to be the splitting character. From the string.Split(char[]) method's documentation page...
Why does Python code use len() function instead of a length method?
...on objects which have a length and use the built-in len() function, which calls it for you, similar to the way you would implement __iter__() and use the built-in iter() function (or have the method called behind the scenes for you) on objects which are iterable.
See Emulating container types for m...
Save ArrayList to SharedPreferences
...Set the values
Set<String> set = new HashSet<String>();
set.addAll(listOfExistingScores);
scoreEditor.putStringSet("key", set);
scoreEditor.commit();
You can also serialize your ArrayList and then save/read it to/from SharedPreferences. Below is the solution:
EDIT:
Ok, below is the sol...
What exactly is an “open generic type” in .NET? [duplicate]
...er a type argument or a generic type defined with unknown type arguments:
All types can be classified as either open types or closed types. An open type is a type that involves type parameters. More specifically:
A type parameter defines an open type.
An array type is an open type if and only if i...
Why does Vim save files with a ~ extension?
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Actually - do I have to have both nobackup and nowritebackup? Is there a way to write a copy of the file as a backup, but not do this write/delete/rename stuff?
– Merlyn Morgan-Graham
Mar 2...
What are unit tests, integration tests, smoke tests, and regression tests?
...re we just check that when the system under test is invoked it returns normally and does not blow up.
Smoke testing is both an analogy with electronics, where the first test occurs when powering up a circuit (if it smokes, it's bad!)...
... and, apparently, with plumbing, where a system of pipes i...
Why is creating a Thread said to be expensive?
... there is a fair bit of work involved:
A large block of memory has to be allocated and initialized for the thread stack.
System calls need to be made to create / register the native thread with the host OS.
Descriptors need to be created, initialized and added to JVM-internal data structures.
It...