The idea of all traits which distinguish between read-only and modifiable sub-type is that eventually the super-type acts somewhat like an expression.
The idea of all traits which distinguish between read-only and modifiable sub-type is that
eventually the super-type acts somewhat like an expression. It might be possible to map
a grapheme with operators, and it might be preferable to avoid having to have the modifiable
operations in the mapped object (cf. Expr
versus Expr.Var
).