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    <p>The difference between them is that destructors emphasise reuse of the cleanup solution by associating it with the type being used, whereas try/finally emphasises one-off cleanup routines. So try/finally is more immediately convenient when you have a unique one-off cleanup requirement associated with the point of use, rather than a reusable cleanup solution that can be associated with a type you're using.</p> <p>I haven't tried this (haven't downloaded a recent gcc for months), but it should be true: with the addition of lambdas to the language, C++ can now have the effective equivalent of <code>finally</code>, just by writing a function called <code>try_finally</code>. Obvious usage:</p> <pre><code>try_finally([] { // attempt to do things in here, perhaps throwing... }, [] { // this always runs, even if the above block throws... } </code></pre> <p>Of course, you have to write try_<code>finally</code>, but only once and then you're good to go. Lambdas enable new control structures.</p> <p>Something like:</p> <pre><code>template &lt;class TTry, class TFinally&gt; void try_finally(const TTry &amp;tr, const TFinally &amp;fi) { try { tr(); } catch (...) { fi(); throw; } fi(); } </code></pre> <p>And there is no link at all between the presence of a GC and a preference for try/finally instead of destructors. C++/CLI has destructors and GC. They're orthogonal choices. Try/finally and destructors are slightly different solutions to the same problem, both deterministic, needed for non-fungible resources.</p> <p>C++ function objects emphasise reusability but make one-off anonymous functions painful. By adding lambdas, anonymous code blocks are now easy to make, and this avoids C++'s traditional emphasis on "forced reusability" expressed through named types.</p>
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    1. POAre there cases where a "finally" construct would be useful in C++?
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    1. USDaniel Earwicker
    1. USDaniel Earwicker
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    1. CONice idea to implementing finally without the language construct. But try_finally should call fi() even if tr() doesn't throw.
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    2. COAlso moved some text to the top so it actually answers the question as well.
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