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throwing exceptions out of a destructor
Most people say never throw an exception out of a destructor - doing so results in undefined behavior. Stroustrup makes the point that "the vector destructor explicitly invokes the destructor for every element. This implies that if an element destructor throws, the vector destruction fails... The...
cannot load such file — zlib even after using rvm pkg install zlib
...ling zlib from apt-get and then reinstalling ruby to not use the rvm directory for zlib.
Here's how do:
$ sudo apt-get install zlib1g-dev
$ rvm reinstall 1.9.3
[Edit] As commenter @chrisfinne mentions, on CentOS/RedHat based systems:
$ sudo yum install zlib-devel
$ rvm reinstall 1.9.3
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how to set desired language in git-gui?
I recently came to git for a project I participate to. I found git gui rather handy (under OSX Snow Leopard) to srtat with but I would much like if it were not localized (in French, in my case). Is there preference or hack to have git gui displayed in english?
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How do I parse JSON with Objective-C?
...ns only as a fallback if you find that class unavailable at runtime.
So, for example:
NSData *returnedData = ...JSON data, probably from a web request...
// probably check here that returnedData isn't nil; attempting
// NSJSONSerialization with nil data raises an exception, and who
// knows how y...
How to convert a table to a data frame
...need -- apparently, the table needs to somehow be converted to a matrix in order to be appropriately translated into a data frame. I found more details on this as.data.frame.matrix() function for contingency tables at the Computational Ecology blog.
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What's the best strategy for unit-testing database-driven applications?
I work with a lot of web applications that are driven by databases of varying complexity on the backend. Typically, there's an ORM layer separate from the business and presentation logic. This makes unit-testing the business logic fairly straightforward; things can be implemented in discrete modul...
How to create index on JSON field in Postgres?
...w do I create an index on a JSON field? I tried it using the -> operator used for hstore but got the following error:
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Is an array an object in java
...ification section 4.3.1 starts off with:
An object is a class instance or an array.
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What is the main difference between Inheritance and Polymorphism?
...to be exactly the same. I was just wondering what the MAIN difference was for my own piece of mind. I know there are a number of similar questions to this but, none I have seen which provide a definitive answer.
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Create list of single item repeated N times
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You can also write:
[e] * n
You should note that if e is for example an empty list you get a list with n references to the same list, not n independent empty lists.
Performance testing
At first glance it seems that repeat is the fastest way to create a list with n identical eleme...