QScopeGuard Class

Disarms the scope guard, so that the function F will not be called at the end of the scope.

The qScopeGuard function can be used to call a function at the end of the scope.

QScopeGuard<F> is a class which sole purpose is to run a function F in its destructor. This is useful for guaranteeing your cleanup code is executed, whether the function is exited normally, exited early by a return statement, or exited by an exception.

If F is a lambda then you cannot instantiate the template directly, therefore the qScopeGuard() helper is provided and QScopeGuard<F> is made a private implementation detail.

Example usage is as follows:

void myComplexCodeWithMultipleReturnPoints(int v)
{
    // The lambda will be executed right before your function returns
    auto cleanup = qScopeGuard([] { code you want executed goes HERE; });

    if (v == -1)
        return;

    int v2 = code_that_might_throw_exceptions();

    if (v2 == -1)
        return;

    (...)
}

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