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What does the “at” (@) symbol do in Python?

... Example class Pizza(object): def __init__(self): self.toppings = [] def __call__(self, topping): # When using '@instance_of_pizza' before a function definition # the function gets passed onto 'topping'. self.toppings.appe...
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How can I force Powershell to return an array when a call only returns one object?

... I actually feel like this is the most clear and safe option. You can reliably use ".Count - ge 1' on the collection or 'Foreach' – Jaigene Kang Jul 11 '17 at 22:24 ...
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Co-variant array conversion from x to y may cause run-time exception

...js[0] = new Foo(); // again legal, with runtime exception In C#, you are allowed to reference an array of objects (in your case, LinkLabels) as an array of a base type (in this case, as an array of Controls). It is also compile time legal to assign another object that is a Control to the array. Th...
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How to check whether a variable is a class or not?

... The inspect.isclass is probably the best solution, and it's really easy to see how it's actually implemented def isclass(object): """Return true if the object is a class. Class objects provide these attributes: __doc__ documentation string __module__ ...
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Can I use Objective-C blocks as properties?

... @CharlieMonroe - Yes you are probably right, but dont you need a dealloc implementation to nil or release the block property without ARC? (its been a while since I used non-ARC) – Robert Mar 31 '13 at 21:58 ...
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How to pass table value parameters to stored procedure from .net code

...to work with it. Assuming your table is a list of integers called "dbo.tvp_Int" (Customize for your own table type) Create this extension method... public static void AddWithValue_Tvp_Int(this SqlParameterCollection paramCollection, string parameterName, List<int> data) { if(paramCollect...
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Why are #ifndef and #define used in C++ header files?

...he header is included, it checks if a unique value (in this case HEADERFILE_H) is defined. Then if it's not defined, it defines it and continues to the rest of the page. When the code is included again, the first ifndef fails, resulting in a blank file. That prevents double declaration of any iden...
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Creating the Singleton design pattern in PHP5

... /** * Singleton class * */ final class UserFactory { /** * Call this method to get singleton * * @return UserFactory */ public static function Instance() { static $inst = null; if ($inst === null) { $inst = new UserFactory(); ...
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Java abstract interface

...blic void interfacing(); public abstract boolean interfacing(boolean really); \___.__/ | '----> nor this, are necessary. } Interfaces and their methods are implicitly abstract and adding that modifier makes no difference. Is there other rules tha...
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How can I get the MAC and the IP address of a connected client in PHP?

... address, you could parse the output of netstat -ie in Linux, or ipconfig /all in Windows. Client IP address You can get the client IP from $_SERVER['REMOTE_ADDR'] Client MAC address The client MAC address will not be available to you except in one special circumstance: if the client is on the s...