Effectively final effective?

[Mark Mahieu]

On 25 Feb 2010, at 09:13, Paulo Levi wrote:

> A aside. It's not the caller that knows how the lambda is going to be used,
> but the function that receives it. You can either forbid unsafe usages, or
> allow them but the function needs a way to say it is safe.
> 
> Just spouting my not very considered opinions. Will shut up now.
> 

That's a perfectly valid line of thinking.  It does make for a more complex approach, but perhaps that's not unwarranted.  BGGA explored some options in that direction.

One big question is where to encode the distinction between 'safe' and 'unsafe'; the temptation is to burden the type system with the responsibility of carrying yet another concept, which isn't without its costs.

Mark