negating bool crashes parser

[mgood]

I was writing some test cases for my Go Ink runtime engine, and testing some scenarios with numeric type coercions.

I noticed most unsupported operations produce an error like:

RUNTIME ERROR: (0.183): Cannot perform operation '-' on String

However, trying to negate a boolean literal results in a stack trace in the parser itself:

{-true}

Unhandled exception. System.Exception: Unexpected operation or number type
   at Ink.Parsed.UnaryExpression.WithInner(Expression inner, String op)
   at Ink.InkParser.ExpressionUnary()
   at Ink.InkParser.Expression(Int32 minimumPrecedence)
   at Ink.InkParser.Expression()
   at Ink.StringParser.Parse[T](SpecificParseRule`1 rule)
   at Ink.InkParser.ConditionExpression()
   at Ink.InkParser.InnerLogic()
   at Ink.StringParser.ParseObject(ParseRule rule)
   at Ink.StringParser.Expect(ParseRule rule, String message, ParseRule recoveryRule)
   at Ink.InkParser.InlineLogic()
   at Ink.StringParser.ParseObject(ParseRule rule)
   at Ink.StringParser.OneOf(ParseRule[] array)
   at Ink.InkParser.InlineLogicOrGlueOrStartTag()
   at Ink.StringParser.ParseObject(ParseRule rule)
   at Ink.StringParser.<>c__DisplayClass58_0.<Optional>b__0()
   at Ink.StringParser.ParseObject(ParseRule rule)
   at Ink.StringParser.Interleave[T](ParseRule ruleA, ParseRule ruleB, ParseRule untilTerminator, Boolean flatten)
   at Ink.InkParser.MixedTextAndLogic()
   at Ink.StringParser.Parse[T](SpecificParseRule`1 rule)
   at Ink.InkParser.LineOfMixedTextAndLogic()
   at Ink.StringParser.ParseObject(ParseRule rule)
   at Ink.StringParser.OneOf(ParseRule[] array)
   at Ink.InkParser.StatementAtLevel(StatementLevel level)
   at Ink.InkParser.<>c__DisplayClass145_0.<StatementsAtLevel>b__0()
   at Ink.StringParser.ParseObject(ParseRule rule)
   at Ink.StringParser.Interleave[T](ParseRule ruleA, ParseRule ruleB, ParseRule untilTerminator, Boolean flatten)
   at Ink.InkParser.StatementsAtLevel(StatementLevel level)
   at Ink.InkParser.Parse()
   at Ink.Compiler.Parse()
   at Ink.Compiler.Compile()
   at Ink.CommandLineTool..ctor(String[] args)
   at Ink.CommandLineTool.Main(String[] args)
Abort trap: 6

This seems unlikely to serve a practical purpose in a real story, but wanted to document it since this results in a big stack trace in the Inky UI if you write it there, and negating boolean values at runtime seems to be supported, e.g.:

{-(2 == 2)}