On 9 May 2013 14:08, Michael Powell wrote: > Hello, > > It's been a little while, but I seem to recall that static variables > can be declared in the scope of a class instance method? Yes. > Next question, I am declaring a lambda function in the scope of a > method to leverage a read-from-channel-to-variable pattern: the read > is the same, agnostic to the channel and variable. > > I am finding that this is somewhat slow, so a couple of thoughts are: > is the lambda even appropriate? I declare it as an auto for starters, > and it resolves every time the function happens. I'm not sure what you mean. Declaring a lambda expression is a compile-time construct, so is 'auto', so there's no run-time resolution. All that happens at run-time is instantiating an object of the closure type and initializing any captured variables (which means either copying the captured variables or binding references to them.) > Can that auto lambda variable be static? It could be, but if you reference-capture any local variables then you'll capture the variables from the first execution of the function, which will be out of scope on the next execution. > Or possibly, I don't think > the problem domain is that dynamic that a handful of helper member > functions wouldn't also do the same job, probably faster too without > the overhead of declaring the lambda autos. There should be no overhead. If you think there is then you'll need to show some example code demonstrating the problem, because I could be misunderstanding what you mean.
