/// <summary>
/// Get an expression which might contain a ternary conditional expression (? :)
/// </summary>
private IExpression Ternary()
{
IExpression expression = Equality();
if (Match(TokenType.QUESTION))
{
IExpression thenExpression = Expression();
Consume(TokenType.COLON, "Expect ':' after conditional expression.");
IExpression elseExpression = Ternary();
expression = new TernaryExpression(expression, thenExpression, elseExpression);
}
return(expression);
}
public object VisitTernaryExpression(TernaryExpression expression)
{
object condition = Evaluate(expression.conditional);
object thenExpression = Evaluate(expression.thenExpression);
object elseExpression = Evaluate(expression.elseExpression);
if (IsTruthy(condition))
{
return(thenExpression);
}
else
{
return(elseExpression);
}
}