Make the Refined constructor private[refined]

[fthomas]

I'd like to make the constructor of Refined private[refined] to ensure that any Refined[T, P] values only contains Ts that satisfy P. But doing so currently fails a tut example:

[tut] *** Error reported at type_aliases.md:18
<console>:28: error: constructor Refined in class Refined cannot be accessed in object $iw
       Square('a', 1)
              ^

The reason for this is that the autoRefineV macro replaces 'a' with Refined('a') in this example and thus calling the constructor outside of the refined package. Can this be done without more black magic?

[fthomas]

One option is to add a (properly documented) public delegate for the private constructor with an ugly or scary name (e.g. unsafeApply) and use that in the macro implementation. This should ensure that nobody circumvents refineV and refineMV accidentally.

[fthomas]

Here is a relevant SO question: http://stackoverflow.com/questions/19170137/using-private-constructor-in-a-macro

Using an ugly named delegate seems to be the only option.