C++11 - noexcept function specifier

Today I would like to present another new feature of C++11 standard - noexcept specifier. This specifier allows to specify function which does not throw any exception. It should be used be used wherever possible to notify user that function should be throw and it makes such function non-throwable self-documented (similar to usage const).

Its usage is similar to usage const function specifier. The difference is that while const function tries to modify data it we have compilation error. In case of noexcept function throws any exception, code compiles, however it std::terminate function is invoked when we achieve throwing exception in such function. To understand it better, take a look on below example: Output of this example is: In point I, we are defining function as non-throwable using noexcept specifier. Such function should not throw, however in our example we are throwing exception in order to present what happens when noexcept function tries to throw exception.

In point II, we are defining additional funciton which we will set up as our terminate function.

We are assigning that funtion as terminate function in point III and replacing default std::terminate function by our terminateFunction(). This function will be invoked when we will try to throw any exception in our noexcept testFunction().

In point IV we are invoking our testFunction() which is noexcept function. However, because our function throws any exception and is specified as noexcept our customized std::terminate function (terminateFunction()) will be invoked and application will abort dumping core file (which is visible in last line of output which we received from out example).

Example used above you can find on our GitHub account here: https://github.com/xmementoit/CppAdventureExamples/tree/master/cpp11/noexcept

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