Syntax definition symbol :label ("Reference") not supported

[tvdstorm]

The syntax definition symbol :label (to refer to a production in syntax rule) is not supported.
Example:

syntax Expr 
  = \bool: Bool | var: Id | bracket "(" Expr ")"
  | not: "!" Expr
  > left and: Expr "&&" Expr
  > left or: Expr "||" Expr; 

Now I should be able to modularly insert new productions into the priority hierarchy. Like so:

syntax Expr
  = :not
  > non-assoc ( lt: Expr "\<" Expr | leq: Expr "\<=" Expr
    | geq: Expr "\>=" Expr | gt: Expr "\>" Expr
    | eq: Expr "==" Expr | neq: Expr "!=" Expr )
  > :and ;

But neither the parser generator (parse errors when parsing expressions), or the type reflector seem to support it (the reference symbols are still in the reified type).

[jurgenvinju]

It's strange, the feature is implemented here:

• rascal/src/org/rascalmpl/library/lang/rascal/grammar/definition/References.rsc

  Line 13 in 2ad766b

  Grammar references(Grammar g)

• rascal/src/org/rascalmpl/library/lang/rascal/grammar/definition/Priorities.rsc

  Line 47 in 2ad766b

  g = references(g);

• rascal/src/org/rascalmpl/library/lang/rascal/syntax/Rascal.rsc

  Line 831 in 2ad766b

  = reference: ":" Name referenced

• rascal/src/org/rascalmpl/library/lang/rascal/grammar/definition/Productions.rsc

  Line 88 in 2ad766b

  case reference(Name n): return \reference(nt, unescape("<n>"));

So this is not a feature request, but rather a bug issue report.

[jurgenvinju]

The reified type is supposed to still have the references in them, but the parser generator should resolve them during priority resolution, and then the right priorities are implemented without introducing a duplicate rule in the original grammar.

[jurgenvinju]

TODO: need to find where this feature is tested.