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Lists: Count vs Count() [duplicate]

...the List itself (derived from ICollection). Internally though, LINQ checks if your IEnumerable implements ICollection and if it does it uses the Count property. So at the end of the day, there's no difference which one you use for a List. To prove my point further, here's the code from Reflector fo...
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When is std::weak_ptr useful?

...d to keep those in memory, so you get rid of the strong pointer. But what if that object is in use and some other code holds a strong pointer to it? If the cache gets rid of its only pointer to the object, it can never find it again. So the cache keeps a weak pointer to objects that it needs to fin...
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How to check if type of a variable is string?

Is there a way to check if the type of a variable in python is a string , like: 20 Answers ...
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How can I verify if one list is a subset of another?

I need to verify if a list is a subset of another - a boolean return is all I seek. 15 Answers ...
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How to check if current thread is not main thread

I need to check if the thread running a certain piece of code is the main (UI) thread or not. How can I achieve this? 9 Ans...
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Remove blank attributes from an Object in Javascript

... test3 : 3, } function clean(obj) { for (var propName in obj) { if (obj[propName] === null || obj[propName] === undefined) { delete obj[propName]; } } } clean(test); If you're concerned about this property removal not running up object's proptype chain, you can also: funct...
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How to ignore xargs commands if stdin input is empty?

... For GNU xargs, you can use the -r or --no-run-if-empty option: --no-run-if-empty -r If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extensi...
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Understanding the basics of Git and GitHub [closed]

...ng with other people, but I don't collaborate with anybody so I don't know if this would be helpful for me. 3 Answers ...
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How to tell if browser/tab is active [duplicate]

I have a function that is called every second that I only want to run if the current page is in the foreground, i.e. the user hasn't minimized the browser or switched to another tab. It serves no purpose if the user isn't looking at it and is potentially CPU-intensive, so I don't want to just waste ...
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How to check if a user likes my Facebook Page or URL using Facebook's API

I think I'm going crazy. I can't get it to work. I simply want to check if a user has liked my page with javascript in an iFrame app. ...