Comments on: Why we need named parameters

By: Jason Olson

Jason Olson — Sat, 20 Dec 2008 07:44:19 +0000

There’s another simple example of why named parameters are nice: boolean parameters. If I have a couple of boolean parameters, what do they mean?

myClass.SomeMethod(true, false, true);

How do I know what that does? Named parameters will help us developers write maintainable code that developers can more easily read after-the-fact without having to rely on Intellisense (after all, I HATE reading code where I _have_ to rely on Intellisense to figure out what the heck is going on)…

By: bogardj

bogardj — Fri, 19 Dec 2008 15:56:01 +0000

@Ben

No, see my previous comment. Overloads and fluent builders are sometimes just hacks around doing named parameters.

By: Ben

Ben — Fri, 19 Dec 2008 15:19:17 +0000

Named parameters would be nice to have. But isn’t this solved by overloads?

By: bogardj

bogardj — Fri, 19 Dec 2008 14:48:37 +0000

@Rob

So the example I had was Regex.IsMatch – both are strings, and should be, but the order is important. Named parameters would eliminate bugs and confusion.

But definitely get your drift – strongly-typed reflection goes a long way to eliminating “magic strings”.

By: Rob

Rob — Fri, 19 Dec 2008 12:44:49 +0000

What I’d like to see is less use of primitive types as parameters to both methods and constructors. A lot of the problems people have with not being able to “remember what should be what” is that method calls like this shouldn’t be taking strings for the names.

By: James Gregory

James Gregory — Fri, 19 Dec 2008 08:27:48 +0000

I think I agree with everyone here. Named parameters shouldn’t stop our regular refactoring efforts, but they will make existing code a lot nicer to use.

By: bogardj

bogardj — Thu, 18 Dec 2008 23:30:31 +0000

@derick

You *may* need to. But since .NET doesn’t have first class hashes like Ruby, long parameter lists are often the only way to go….sometimes. And I don’t know your experience with parameter objects, but mine hasn’t been that great.

Also, when two parameters are of the same type, it can be tough to remember what should be what.

By: Ben Scheirman

Ben Scheirman — Thu, 18 Dec 2008 19:55:19 +0000

I agree with Derik, but it would still be nice to have. We have loads of APIs out there that look like this today.

Attributes have this, why can’t methods?

By: Joe

Joe — Thu, 18 Dec 2008 18:24:01 +0000

I concur with Mr. Bailey.

By: derick.bailey

derick.bailey — Thu, 18 Dec 2008 14:29:18 +0000

“especially when the number of arguments grows in a method call”

isn’t that usually a design smell to say that you may need to consolidate parameters into DTOs, or re-examine your SoC/SRP?