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Memory management in Qt?
I'm quite new to Qt and am wondering on some basic stuff with memory management and the life of objects. When do I need to delete and/or destroy my objects? Is any of this handled automatically?
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Is there a way to pass optional parameters to a function?
...a way in Python to pass optional parameters to a function while calling it and in the function definition have some code based on "only if the optional parameter is passed"
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How to trigger event when a variable's value is changed?
...ever the value of a field is going to change.
You can have your own EventHandler delegate or you can use the famous System.EventHandler delegate.
Usually there's a pattern for this:
Define a public event with an event handler delegate (that has an argument of type EventArgs).
Define a protected ...
What are fixtures in programming?
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The purpose of a test fixture is to ensure that there is a well known
and fixed environment in which tests are run so that results are
repeatable. Some people call this the test context.
Examples of fixtures:
Loading a database with a specific, known set of data
Erasing a hard ...
Create list of single item repeated N times
...ng'] * len(columns)
Mutable items
I've used Python for a long time now, and I have never seen a use-case where I would do the above with a mutable instance. Instead, to get, say, a mutable empty list, set, or dict, you should do something like this:
list_of_lists = [[] for _ in columns]
The un...
START_STICKY and START_NOT_STICKY
What is the difference between START_STICKY and START_NOT_STICKY while implementing services in android? Could anyone point out to some standard examples.. ?
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How to pass arguments and redirect stdin from a file to program run in gdb?
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Pass the arguments to the run command from within gdb.
$ gdb ./a.out
(gdb) r < t
Starting program: /dir/a.out < t
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Can I have multiple :before pseudo-elements for the same element?
...pseudo-element at any time. (This means an element can have both a :before and an :after pseudo-element — it just cannot have more than one of each kind.)
As a result, when you have multiple :before rules matching the same element, they will all cascade and apply to a single :before pseudo-elemen...
Microsoft Roslyn vs. CodeDom
...o Roslyn, but is only marginally related. Essentially, CodeDom is a simple and (somewhat) langage agnostic way to generate code that was added in .NET 1.0 to support designers (a la WinForms). Because CodeDom was an attempt at providing a unified model that can generate code in C#, VB, and other lan...
Razor View Engine : An expression tree may not contain a dynamic operation
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Seems like your view is typed dynamic. Set the right type on the view and you'll see the error go away.
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