private string evalOperatorSubToken(int precedence, TreeToken subToken)
{
bool brackets = precedence > OperatorProperties.GetPrecedence(subToken);
string expr = subToken.Evaluate(this);
if (brackets)
{
expr = $"{ParserSymbols.LBracket}{expr}{ParserSymbols.RBracket}";
}
return(expr);
}
public override string EvaluateOperator(OperatorToken token)
{
if (token is SignOperatorToken)
{
return(evalSignOperator(token as SignOperatorToken));
}
int precedence = OperatorProperties.GetPrecedence(token);
string exprLeft = evalOperatorSubToken(precedence, token.SubTokens[0]);
string exprRight = evalOperatorSubToken(precedence, token.SubTokens[1]);
return(exprLeft + token.Symbol + exprRight);
}
private string evalSub(StructToken token, int subIndex)
{
TreeToken subToken = token.SubTokens[subIndex];
int precedence = OperatorProperties.GetPrecedence(token);
bool brackets = precedence > OperatorProperties.GetPrecedence(subToken);
string expr = subToken.Evaluate(this);
if (brackets)
{
expr = $"<mo>(</mo>{expr}<mo>)</mo>";
}
return(expr);
}
public PFNViewModel(IPFNEngine pFNEngine, OperatorProperties operatorProperties)
{
PFNEngine = pFNEngine;
OperatorProperties = operatorProperties;
EvaluateCommand = new RelayCommand(ExecuteEvaluateCommand, ValidateInput);
}
