Lambda or extension method reference [Answered]
If you have an extension which maps a type A to another type B and you have an enumerable of type A which you want to turn into an enumerable of type B, should you prefer
.Select(x => x.ToB()) or .Select(Extensions.ToB)? The first I assume allocates an extra unnecessary lambda which the second doesn't?7 Replies
I believe there is a very minor performance gain by using the method group over the explicit lambda
however, you shouldn't care about performance until you have a reason to and have identified bottlenecks
I personally think using the method group looks much nicer, so that's what I use when I can
I kind of think the opposite, but good to know
Having to write the name of an extension class feels... weird
i agree - this might be one of the places where i make an exception
it's ultimately up to your preference, in any situation where the performance mattered it would be outshined by using LINQ to begin with
Fair
The first I assume allocates an extra unnecessary lambda which the second doesn't?No. In fact, up until recently, the first would be more memory-friendly This is yet another example of trying to optimize based on an implementation detail In both of these cases, you need an instance of a
Func<T1, T2>
One creates a lambda, the other uses a method group. In either case, you need to allocate memoryFair point
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