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Why does C# forbid generic attribute types?

...y, write lesser code than otherwise required, get benefits of polymorphism etc. //an interface which means it can't have its own implementation. //You might need to use extension methods on this interface for that. public interface ValidatesAttribute<T> { T Value { get; } //or whatever t...
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Find a value anywhere in a database

...E like case when len(@ColumnName) > 0 then @ColumnName else '%' end order by c.TABLE_NAME, c.ORDINAL_POSITION declare @table_schema sysname , @table_name sysname , @column_name sysname , @data_type sysname , @exists nvarchar(4000) -- Can be max for SQL2005+ , @sql n...
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How to import a Python class that is in a directory above?

... exists. Two dots means up one package level. Three dots is up two levels, etc. So if you execute from . import mod from a module in the pkg package then you will end up importing pkg.mod. If you execute from ..subpkg2 import mod from within pkg.subpkg1 you will import pkg.subpkg2.mod. The specifica...
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What is “lifting” in Haskell?

...Suppose you find that a lot of uses of Foo take numeric types (Int, Double etc) and you keep having to write code that unwraps these numbers, adds or multiplies them, and then wraps them back up. You can short-circuit this by writing the unwrap-and-wrap code once. This function is traditionally ca...
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how to prevent “directory already exists error” in a makefile when using mkdir

...BJDIR) You should see here the usage of the | pipe operator, defining an order only prerequisite. Meaning that the $(OBJDIR) target should be existent (instead of more recent) in order to build the current target. Note that I used mkdir -p. The -p flag was added compared to the example of the doc...
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What exactly are “spin-locks”?

... When you use regular locks (mutexes, critical sections etc), operating system puts your thread in the WAIT state and preempts it by scheduling other threads on the same core. This has a performance penalty if the wait time is really short, because your thread now has to wait for ...
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What 'additional configuration' is necessary to reference a .NET 2.0 mixed mode assembly in a .NET 4

... In order to use a CLR 2.0 mixed mode assembly, you need to modify your App.Config file to include: <?xml version="1.0"?><configuration> <startup useLegacyV2RuntimeActivationPolicy="true"> <supportedRunt...
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Detect when a window is resized using JavaScript ?

... ", window.innerWidth, "px"); } window.onresize = resize; <p>In order for this code snippet to work as intended, you will need to either shrink your browser window down to the size of this code snippet, or fullscreen this code snippet and resize from there.</p> ...
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How do you add swap to an EC2 instance?

...something higher. To enable it by default after reboot, add this line to /etc/fstab: /var/swap.1 swap swap defaults 0 0 share | improve this answer | foll...
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How to quickly and conveniently disable all console.log statements in my code?

...ourse there are many more functions in Firebug, like trace, profile, time, etc. They can be added to the list if you use them in your code. You can also check if the debugger has those special methods or not (ie, IE) and zero out the ones it does not support: if(window.console && !console...