public object VisitTertiaryExpr(Expr.Tertiary expr)
{
var condition = Evaluate(expr.Condition);
if (IsTruthy(condition))
{
return(Evaluate(expr.Then));
}
else
{
return(Evaluate(expr.Else));
}
}
private Expr Expression()
{
Expr expr = Equality();
if (Match(TokenType.IfThen))
{
Expr then = Expression();
Consume(TokenType.Else, "Expected ':' after then-branch of ?.");
Expr @else = Expression();
expr = new Expr.Tertiary(expr, then, @else);
}
return(expr);
}
public string VisitTertiaryExpr(Expr.Tertiary expr)
{
return($"{expr.Condition.Accept(this)} ? {expr.Then.Accept(this)} : {expr.Else.Accept(this)}");
}
public string VisitTertiaryExpr(Expr.Tertiary expr)
{
return(Parenthesize("?:", expr.Condition, expr.Then, expr.Else));
}