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Why is there a difference in checking null against a value in VB.NET and C#?
...I don't know yet". Then the comparison of 5 to "I don't know yet". is naturally "I don't know yet"; ie NULL. This has the additional advantage of mirroring the behaviour of NULL in (most if not all) SQL databases. This is also a more standard (than C#'s) interpretation of three-valued logic, as expl...
libxml/tree.h no such file or directory
...wered Sep 15 '09 at 18:21
Matt BallMatt Ball
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Where is my .vimrc file?
I have been using Vim , and I would really like to save my settings. The problem I am having is that I cannot find my .vimrc file, and it is not in the standard /home/user/.vimrc location. How might I find this file?
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Focus-follows-mouse (plus auto-raise) on Mac OS X
...defaults write org.x.X11 wm_ffm -bool true
Apparently there's a program called CodeTek Virtual Desktop that'll emulate it systemwide, but it costs $$ (and they never got a version out for OSX Leopard).
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What is `related_name` used for in Django?
... back to your model.
If you don't specify a related_name, Django automatically creates one using the name of your model with the suffix _set, for instance User.map_set.all().
If you do specify, e.g. related_name=maps on the User model, User.map_set will still work, but the User.maps. syntax is ob...
Targeting .NET Framework 4.5 via Visual Studio 2010
Today I installed the .NET Framework 4.5 on my machine expecting to be able to use it from Visual Studio 2010, since it's just a minor update that should't pose problems for Visual Studio 2010. Unfortunately I am not, even manually removing certain 4.0 and adding the corresponding 4.5 assemblies r...
Get all column names of a DataTable into string array using (LINQ/Predicate)
...ase post it as a new question and include details of your code. But essentially: A DataGrid is not the same as a DataTable.
– Daniel Hilgarth
May 17 '13 at 8:08
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How can I remove an element from a list?
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I don't know R at all, but a bit of creative googling led me here: http://tolstoy.newcastle.edu.au/R/help/05/04/1919.html
The key quote from there:
I do not find explicit documentation for R on how to remove elements from lists, but trial...
Why is null an object and what's the difference between null and undefined?
...nown what the value is.
One thing to remember is that null is not, conceptually, the same as false or "" or such, even if they equate after type casting, i.e.
name = false;
You: What is name?
JavaScript: Boolean false.
name = '';
You: What is name?
JavaScript: Empty string
*: name in this context...
Is there a simple way to delete a list element by value?
...('b')
>>> print(a)
['a', 'c', 'd']
Mind that it does not remove all occurrences of your element. Use a list comprehension for that.
>>> a = [10, 20, 30, 40, 20, 30, 40, 20, 70, 20]
>>> a = [x for x in a if x != 20]
>>> print(a)
[10, 30, 40, 30, 40, 70]
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