问题
I've looked at both the Named Parameter Idiom and the Boost::Parameter library. What advantages does each one have over the other? Is there a good reason to always choose one over the other, or might each of them be better than the other in some situations (and if so, what situations)?
回答1:
Implementing the Named Parameter Idiom is really easy, almost about as easy as using Boost::Parameter, so it kind of boils down to one main point.
-Do you already have boost dependencies? If you don't, Boost::parameter isn't special enough to merit adding the dependency.
Personally I've never seen Boost::parameter in production code, 100% of the time its been a custom implementation of Named Parameters, but that's not necessarily a good thing.
回答2:
Normally, I'm a big fan of Boost, but I wouldn't use the Boost.Parameter library for a couple of reasons:
- If you don't know what's going on, the call looks like you're assigning a value to a variable in the scope on the calling function before making the call. That can be very confusing.
- There is too much boilerplate code necessary to set it up in the first place.
回答3:
Another point, while I have never used Named Parameter Idiom, I have used Boost Parameter for defining up to 20 optional arguments. And, my compile times are insane. What used to take a couple seconds, now takes 30sec. This adds up if you have a library of stuff that use your one little application that you wrote using boost parameter. Of course, I might be implementing it wrongly, but I hope this changes, because other than that, i really like it.
回答4:
The Named Parameter idiom is a LOT simpler. I can't see (right now) why we would need the complexity of the Boost::Parameter library. (Even the supposed "feature" Deduced parameters, seems like a way to introduce coding errors ;) )
回答5:
You probably don't want Boost.Parameter for general application logic so much as you would want it for library code that you are developing where it can be quite a time saver for clients of the library.
回答6:
Never heard of either, but reviewing the links, named parameter is WAY easier and more obvious to understand. I'd pick it in a heartbeat over the boost implementation.
来源：https://stackoverflow.com/questions/203667/c-named-parameter-idiom-vs-boostparameter-library