private bool IsInfixBinary(StringToken token, Operator[] possibleOperators)
{
if (!possibleOperators.Any(x => x.Fixity == Fixity.Infix && x.Arity == Arity.Binary))
{
return(false);
}
var isPrecededByCloseBracket = grammarService.ClosePriorityBracket.Denotations.Contains(token.Previous);
var isFollowedByOpenBracket = grammarService.OpenPriorityBracket.Denotations.Contains(token.Next);
// like 5 + 2
// ^
var isInfixBinaryCase1 = grammarService.IsOperand(token.Previous) && grammarService.IsOperand(token.Next);
// like 5 + (2 + 3)
// ^
var isInfixBinaryCase2 = grammarService.IsOperand(token.Previous) &&
isFollowedByOpenBracket;
// like (2 + 3) + 5
// ^
var isInfixBinaryCase3 = isPrecededByCloseBracket &&
grammarService.IsOperand(token.Next);
// like 5! + 3
// ^
var isInfixBinaryCase4 = grammarService.IsOperator(token.Previous) &&
grammarService.IsOperand(token.Next) &&
grammarService.IsUniqueByFixity(token.Previous, Fixity.Postfix);
// like (1 + 2) + (3 + 4)
// ^
var isInfixBinaryCase5 = isPrecededByCloseBracket &&
grammarService.IsOperator(token.Current) &&
isFollowedByOpenBracket;
return(isInfixBinaryCase1 ||
isInfixBinaryCase2 ||
isInfixBinaryCase3 ||
isInfixBinaryCase4 ||
isInfixBinaryCase5);
}
