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How to specialize std::hash::operator() for user-defined type in unordered containers?
To support user-defined key types in std::unordered_set<Key> and std::unordered_map<Key, Value>
one has to provide operator==(Key, Key) and a hash functor:
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How to set variables in HIVE scripts
...where day >= ${hiveconf:CURRENT_DATE}
similarly, you could pass on command line:
% hive -hiveconf CURRENT_DATE='2012-09-16' -f test.hql
Note that there are env and system variables as well, so you can reference ${env:USER} for example.
To see all the available variables, from the command line, ...
Fastest way to check if a string matches a regexp in ruby?
... avoids object allocations performed by other methods such as Regexp#match and =~:
Regexp#match?
Added Regexp#match?, which executes a regexp match without creating a back reference object and changing $~ to reduce object allocation.
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What is an example of the simplest possible Socket.io example?
So, I have been trying to understand Socket.io lately, but I am not a supergreat programmer, and almost every example I can find on the web (believe me I have looked for hours and hours), has extra stuff that complicates things. A lot of the examples do a bunch of things that confuse me, or connect ...
How to link a folder with an existing Heroku app
I have an existing Rails app on GitHub and deployed on Heroku. I'm trying to set up a new development machine and have cloned the project from my GitHub repository. However, I'm confused as to how to link this folder up to Heroku. Originally, I used the heroku create command, but obviously I don't...
Error TF30063: You are not authorized to access … \DefaultCollection
...most of my projects. When I use my on-premises TFS after using TFS preview and go back to using TFS preview, I get this error:
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Do the parentheses after the type name make a difference with new?
...e.
Sometimes the memory returned by the new operator will be initialized, and sometimes it won't depending on whether the type you're newing up is a POD (plain old data), or if it's a class that contains POD members and is using a compiler-generated default constructor.
In C++1998 there are 2 typ...
Ignore mouse interaction on overlay image
I have a menu bar with hover effects, and now I want to place a transparent image with a circle and a "handdrawn" text over one of the menu items. If I use absolute positioning to place the overlay image above the menu item, the user will not be able to click the button and the hover effect will not...
Which Android IDE is better - Android Studio or Eclipse? [closed]
I'm starting to develop for Android. Which IDE should I use - Android Studio or Eclipse sdk?
I would like to know which one is better.
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ConcurrentHashMap vs Synchronized HashMap
...ference between using the wrapper class, SynchronizedMap , on a HashMap and ConcurrentHashMap ?
12 Answers
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