ISSUES

## Issues

- infix chain more nicely with implicits, than implicits with
  implicits. hurdle e.g.:
  https://github.com/TiarkRompf/virtualization-lms-core/commit/d92799fdcda352fd7bf9887990844e15550c3516#diff-4c255b088661c91c9d0a1d444e7df7b9R42

  arithmetic with numeric widening is another example: both
  int * double and double * int need to be handled.
  variables will add further complication, so we have: (Var + Rep + T) x (Int, Double, ...).

  for systems-level code, a possible option is to just not support
  widening (i.e. require x.toDouble), but for Delite this doesn't look 
  like an option.

  https://github.com/TiarkRompf/virtualization-lms-core/commit/c6c77f8e6325c5dff26eb0fac6a61087eed7637f

- the new scala-virtualized has some anyref-specific virtualization
  (such as clone), and these seem to not mesh well with rep types. seems
  like this triggers an error in type-checking after macro-expansion.
  hurdle e.g.:
  https://github.com/TiarkRompf/virtualization-lms-core/commit/d92799fdcda352fd7bf9887990844e15550c3516#diff-4c255b088661c91c9d0a1d444e7df7b9R32

- in the new scala-virtualized, scala.Predef does not mix in EmbeddedControls,
  so adding @virtualize to a trait that does not inherit from EmbeddedControls
  caused method not found errors.




## General todo items

- core functionality
- performance
- pattern matching
- refined manifests
- source context
- structs
- scopes