/// <summary>
/// Execute each expression.
/// </summary>
/// <returns></returns>
public object VisitFor(ForExpr expr)
{
expr.Start.Evaluate(this);
expr.DoContinueRunning = true;
expr.DoBreakLoop = false;
expr.DoContinueLoop = false;
var result = expr.Condition.Evaluate(this) as LObject;
expr.DoContinueRunning = EvalHelper.IsTrue(result);
while (expr.DoContinueRunning)
{
if (expr.Statements != null && expr.Statements.Count > 0)
{
foreach (var stmt in expr.Statements)
{
stmt.Evaluate(this);
this.Ctx.Limits.CheckLoop(expr);
// If Break statment executed.
if (expr.DoBreakLoop)
{
expr.DoContinueRunning = false;
break;
}
// Continue statement.
else if (expr.DoContinueLoop)
break;
}
}
else break;
// Break loop here.
if (expr.DoContinueRunning == false)
break;
expr.Increment.Evaluate(this);
result = expr.Condition.Evaluate(this) as LObject;
expr.DoContinueRunning = EvalHelper.IsTrue(result);
}
return LObjects.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 For(Expr start, Expr condition, Expr increment, TokenData token)
{
var exp = new ForExpr();
exp.Start = start;
exp.Condition = condition;
exp.Increment = increment;
SetupContext(exp, token);
return exp;
}
/// <summary>
/// Visits the for statement tree.
/// </summary>
/// <param name="forExpr"></param>
public object VisitFor(ForExpr expr)
{
_callBackOnNodeStart(expr);
expr.Start.Visit(this);
expr.Condition.Visit(this);
expr.Increment.Visit(this);
foreach (var stmt in expr.Statements)
{
stmt.Visit(this);
}
return null;
}