'$' conflict between 'unaryTripleExpr' and 'tripleExprLabel'

[mistermboy]

Current grammar forces us to do things like this:

:User {
 $$:name  schema:name .
}
:Employee {
  &$:name ;
}

Instead of:

:User {
 $:name  schema:name .
}
:Employee {
  &:name ;
}

The problem is that there is a conflict with '$' token between this two rules:

• [40] unaryTripleExpr ::= ('$' tripleExprLabel)? (tripleConstraint | bracketedTripleExpr) | include
• [42] tripleExprLabel ::= '$' (iri | blankNode)

This also affects to rule number [50]:

• [50] include::= '&' tripleExprLabel

'$' is repeated and should be removed in the rule [42]. If we removed '$' in the rule [40] we don't fix the conflict with the rule [50].

This problem is located in the master branch grammar and also in the shex2.1 branch grammar , but seems to be good in ShExDoc.g4 file

[ericprud]

we should s/\$/$$$/g so it parses spam subject lines like "earn $$$ now!"
though i guess your point is that we're already claiming to parse "$$".

The normative doc is the spec which specifies as a tripleExprLabel without a '$'. We need to make the grammar branch align with that.