Re:You’re better off using Exceptions
by quietbritishjim on Monday February 03, 2020 @12:20PM
(#22226319)
That is like C++ destructors, which are called deterministically when they go out of scope (again with no "try" syntax). They can unlock mutexes, close files, etc. But unlike what you describe, there is no need to put anything at the end of the function: instead, the fact that you have instantiated an object already guarantees that its destructor will be called later. This is called RAII, short for "resource acquisition is initialisation".
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Re:You’re better off using Exceptions
by waynecochran on Monday February 03, 2020 @01:43PM
(#22227426)
Yes... RAII is handy, but it doesn’t save you from checking EOF logic in my example.
Re:You’re better off using Exceptions
by safety-second on Monday February 03, 2020 @02:41PM
(#22228106)
You could use a File class that throws on EOF, but that would be a really bad idea for C++ since throw/catch are very expensive.
Re:You’re better off using Exceptions
by quietbritishjim on Monday February 03, 2020 @05:49PM
(#22230231)
Exceptions are expensive compared to a simple function call, but I imagine they're cheap compared to operations that read from disk. Certainly one exception per file close is not going to hurt.