ValueOption warnings

Hello again,

I’m getting following warnings from BuildResult it seems related to ValueOption:

"non terminal [GROUP-COMPARATOR-StringConcatExpr] is never used."
"non terminal [GROUP-TO[d]-AdditiveExpr] is never used."
"non terminal [GROUP-Argument-ExtraArgumentList] is never used."

Also,

I have the following rule:

[Production("RangeExpr: AdditiveExpr (TO [d] AdditiveExpr)?")]
public object RangeExpr(object additiveExpr, ValueOption<Group<XPathToken, object>> optionalGroup)

When I delete the optional group clause it works without problem, but when I add the rule, the program gives the following exception. Note that, the parsed string does not contain anything related to the optional group clause

OUTCH Object of type 'sly.parser.parser.ValueOption`1[System.Object]' cannot be converted to type 
'sly.parser.parser.ValueOption`1[sly.parser.parser.Group`2[netSchematron.XPathToken,System.Object]]'. 
calling RangeExpr__AdditiveExpr_GROUP-TO[d]-AdditiveExpr? =>  RangeExpr

We have talked about this exception before in this issue however, I can not seem to identify the lexer problem this time.

I think the warnings and the exception are connected.

[b3b00]

thanks for the test case. i now have a failing unit test (see it on branch bugfix/#104). I see what hapen. And will try to solve it later. For now my best proposal is to get rid of the group and use another nonterminal that you can optioned

XPath: AndExpr newNonTerminal ? newNonTerminal : COMPARATOR AndExpr

it’s exactly what the group does but it fails on the particular case of an empty option.

[aeb-dev]

seems to be working thank you very much.