message: Use correct spacing around type annotation colon
diff: @@ -378,11 +378,11 @@ A struct containing an `@if` rule cannot be fixed size.
  FIXME what if the if only depends on a type argument?
  ```
  -sizeof(if X { type1 } else { type2 }) ==
  - if X sizeof(type1) else sizeof(type2)
  +sizeof(if x { type1 } else { type2 }) ==
  + if x sizeof(type1) else sizeof(type2)
  -interp(if X { type1 } else { type2 }) ==
  - if X interp(type1) else interp(type2)
  +interp(if x { type1 } else { type2 }) ==
  + if x interp(type1) else interp(type2)
  ```
  ### Choice Types
  