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Proper use of beginBackgroundTaskWithExpirationHandler
...l need to wrap it in a background task. It's also very important that you call endBackgroundTask when you're finished - otherwise the app will be killed after its allotted time has expired.
Mine tend look something like this:
- (void) doUpdate
{
dispatch_async(dispatch_get_global_queue(DISPAT...
Namespace not recognized (even though it is there)
... page.
This is a problem in Visual Studio (I would even go so far as to call it a bug). AutoMapper requires assemblies that are excluded from the .NET Framework 4 Client Profile. Since your project is using that version of the framework it breaks.
A similar error will propagate to the build pro...
How to know if two arrays have the same values
..., i.e. ['a', 'b'] and ['a,b']. I would only recommend this technique for small throwaway scripts.
– alex
Mar 7 '16 at 16:23
1
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Multiple Inheritance in PHP
...tMessage class, and sending algorithm is delegated to dispatcher. This is called Strategy Pattern, you can read more on it here.
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A semantics for Bash scripts?
...patchwork together little scripts that appear to work. However, I don't really know what's going on, and I was hoping for a more formal introduction to Bash as a programming language. For example: What is the evaluation order? what are the scoping rules? What is the typing discipline, e.g. is ever...
Why is GHC so large/big?
...
It's a bit silly really. Every library that comes with GHC is provided in no less than 4 flavours:
static
dynamic
profiled
GHCi
The GHCi version is just the static version linked together in a single .o file. The other three versions all ...
Change column type from string to float in Pandas
...ost) any other type (even if it's not necessarily sensible to do so). Also allows you to convert to categorial types (very useful).
infer_objects() - a utility method to convert object columns holding Python objects to a pandas type if possible.
convert_dtypes() - convert DataFrame columns to the ...
Numpy - add row to array
...2, 0]])
X = array([[0, 1, 2], [1, 2, 0], [2, 1, 2], [3, 2, 0]])
add to A all rows from X where the first element < 3:
import numpy as np
A = np.vstack((A, X[X[:,0] < 3]))
# returns:
array([[0, 1, 2],
[0, 2, 0],
[0, 1, 2],
[1, 2, 0],
[2, 1, 2]])
...
Migration: Cannot add foreign key constraint
...signed();
$table->string('priority_name');
$table->smallInteger('rank');
$table->text('class');
$table->timestamps('timecreated');
});
Schema::table('priorities', function($table) {
$table->foreign('user_id')->references('id')->on('...
Can a C# lambda expression have more than one statement?
...
(I'm assuming you're really talking about multiple statements rather than multiple lines.)
You can use multiple statements in a lambda expression using braces, but only the syntax which doesn't use braces can be converted into an expression tree:
...