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What's the difference between struct and class in .NET?
...or a struct, that means that the variable contains the entire struct, with all its fields.
A variable containing a reference type contains a pointer, or a reference to somewhere else in memory where the actual value resides.
This has one benefit, to begin with:
value types always contains a valu...
How to get the absolute coordinates of a view
...solute screen pixel coordinates of the top left corner of a view. However, all methods I can find such as getLeft() and getRight() don't work as they all seem to be relative to the parent of the view, thus giving me 0 . What is the proper way to do this?
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How do you query for “is not null” in Mongo?
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This will return all documents with a key called "IMAGE URL", but they may still have a null value.
db.mycollection.find({"IMAGE URL":{$exists:true}});
This will return all documents with both a key called "IMAGE URL" and a non-null value.
d...
Is there a list of Pytz Timezones?
I would like to know what are all the possible values for the timezone argument in the Python library pytz. How to do it?
7...
Git and nasty “error: cannot lock existing info/refs fatal”
...his answer seems to help a lot of people, I dug a little bit into what actually happens here. What this will do is remove references to remote branches in the folder .git/refs/remotes/origin. So this will not affect your local branches and it will not change anything remote, but it will update the l...
Android Studio - local path doesn't exist
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I originally saw this error after upgrading from 0.2.13 to 0.3. These instructions have been updated for the release of Android Studio 0.5.2. These are the steps I completed to resolve the issue.
1.In build.gradle make sure gradle i...
Amazon products API - Looking for basic overview and information
...me:
The API you're interested in is the Product Advertising API (PA). It allows you programmatic access to search and retrieve product information from Amazon's catalog. If you're having trouble finding information on the API, that's because the web service has undergone two name changes in recent...
Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign
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This problem is usually caused by one of the following
null values being returned for columns not set to AllowDBNull
duplicate rows being returned with the same primary key.
a mismatch in column definition (e.g. size of char fields) between t...
git ignore vim temporary files
...t is the correct way to make git ignore temporary files produced by vim in all directories (either globally across the system or locally for a single project)?
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Initialization of all elements of an array to one default value in C++?
...[100] = {-1};
says "set the first element to -1 and the rest to 0" since all omitted elements are set to 0.
In C++, to set them all to -1, you can use something like std::fill_n (from <algorithm>):
std::fill_n(array, 100, -1);
In portable C, you have to roll your own loop. There are comp...