Feature request: Add runtime exception check instead of error "compile-time refinement only works with literals"

Hi, I’m posting this feature request after a small e-mail exchange with @fthomas

The code

for (i <-  -1 to 3)
  println(refineMV[Positive](i))

currently results in compile-time refinement only works with literals error.

I suggest that instead this will result in a runtime check, meaning four possible cases:

1. Compile time check pass for literal (no runtime check required)

     println(refineMV[Positive](1))
   

   Prints outs: 1

2. Compile time check fail for literal

     println(refineMV[Positive](0))
   

3. Compile time check could not run, so running runtime check instead, which passed

   for (i <-  1 to 3)
     println(refineMV[Positive](i)) 
   

   Prints outs: 1 2 3

4. Compile time check could not run, so running runtime check instead, which failed and throws exception

   for (i <-  -1 to 3)
     println(refineMV[Positive](i))  //Throws exception
   

Note: Instead of modifying refineMV you may wish to keep it as is, and add another flavor (something like refineMVRE [Macro Verify, Runtime Exception], or whatever acronym you wish). However, I don’t think you should. Keep it simple with the least functions possible.

Thanks, Oron

[ysusuk]

@fthomas i’m trying to make this one https://github.com/fthomas/refined/compare/topic/unsafeFrom2 work

[soronpo]

@ysusuk I created a solution using the singleton-ops library, which is called TwoFace and Checked values. You can read about it in the following link: https://contributors.scala-lang.org/t/twoface-values-closing-the-gap-between-run-compile-time-functionality/869