/// <summary>
/// Visits the compare expression tree
/// </summary>
/// <param name="exp"></param>
public object VisitCompare(CompareExpr exp)
{
_callBackOnNodeStart(exp);
_callBackOnNodeStart(exp.Left);
_callBackOnNodeStart(exp.Right);
return null;
}
/// <summary>
/// Creates a unary expression with symbol scope, context, script refernce set.
/// </summary>
/// <param name="name"></param>
/// <param name="token"></param>
/// <returns></returns>
public static Expr Compare(Expr left, Operator op, Expr right, TokenData token)
{
var exp = new CompareExpr();
exp.Left = left;
exp.Op = op;
exp.Right = right;
SetupContext(exp, token);
return exp;
}
/// <summary>
/// Evaluate > >= != == less less than
/// </summary>
/// <returns></returns>
public static object EvalCompare(CompareExpr expr)
{
// Validate
object result = null;
var node = expr;
var op = expr.Op;
var left = (LObject)expr.Left.Evaluate();
var right = (LObject)expr.Right.Evaluate();
// Both double
if (left.Type == LTypes.Number && right.Type == LTypes.Number)
result = EvalHelper.CompareNumbers(node, (LNumber)left, (LNumber)right, op);
// Both strings
else if (left.Type == LTypes.String && right.Type == LTypes.String)
result = EvalHelper.CompareStrings(node, (LString)left, (LString)right, op);
// Both bools
else if (left.Type == LTypes.Bool && right.Type == LTypes.Bool)
result = EvalHelper.CompareBools(node, (LBool)left, (LBool)right, op);
// Both dates
else if (left.Type == LTypes.Date && right.Type == LTypes.Date)
result = EvalHelper.CompareDates(node, (LDate)left, (LDate)right, op);
// Both Timespans
else if (left.Type == LTypes.Time && right.Type == LTypes.Time)
result = EvalHelper.CompareTimes(node, (LTime)left, (LTime)right, op);
// 1 or both null
else if (left == LObjects.Null || right == LObjects.Null)
result = EvalHelper.CompareNull(left, right, op);
// Day of week ?
else if (left.Type == LTypes.DayOfWeek || right.Type == LTypes.DayOfWeek)
result = EvalHelper.CompareDays(node, left, right, op);
// Units
//else if (left.Type == LTypes.Unit || right.Type == LTypes.Unit)
else if (left.Type.Name == "LUnit" || right.Type.Name == "LUnit")
result = EvalHelper.CompareUnits(node, (LUnit)((LClass)left).Value, (LUnit)((LClass)right).Value, op);
return result;
}
/// <summary>
/// Creates a unary expression with symbol scope, context, script refernce set.
/// </summary>
/// <param name="name"></param>
/// <param name="token"></param>
/// <returns></returns>
public Expr ToCompareExpr(Expr left, Operator op, Expr right, TokenData token)
{
var exp = new CompareExpr(left, op, right);
this.SetupContext(exp, token);
return exp;
}