public static IEnumerable <SearchItem> If(SearchExpressionContext c)
{
if (c.args.Length < 2)
{
c.ThrowError("Not enough parameters for if");
}
bool cond = false;
foreach (var item in c.args[0].Execute(c))
{
if (item == null)
{
yield return(null);
}
else
{
cond |= SearchExpression.IsTrue(item);
if (!cond)
{
break;
}
}
}
if (cond)
{
foreach (var item in c.args[1].Execute(c))
{
yield return(item);
}
}
else if (c.args.Length == 2)
{
// Nothing to do.
}
else
{
foreach (var item in c.args[2].Execute(c))
{
yield return(item);
}
}
}
public static IEnumerable <SearchItem> IsTrue(SearchExpressionContext c)
{
foreach (var e in c.args)
{
bool isTrue = false;
foreach (var item in e.Execute(c))
{
if (item == null)
{
yield return(null);
}
else
{
isTrue |= SearchExpression.IsTrue(item);
if (!isTrue)
{
break;
}
}
}
yield return(SearchExpression.CreateItem(isTrue, c.ResolveAlias(e, "IsTrue")));
}
}
public static IEnumerable <SearchItem> ToBoolean(SearchExpressionContext c)
{
return(c.args.SelectMany(e => e.Execute(c)).Select(item => SearchExpression.CreateItem(SearchExpression.IsTrue(item))));
}