Can you set/update a value in real-time within a LINQ statement during iteration?

Question

Based on a proposed answer to my other question here... is it possible to update a variable during LINQ enumeration so you can use it as part of a test?

For instance, is anything like this possible?

// Assume limitItem is of type Foo and sourceList is of type List<Foo> 

// Note the faux attempt to set limitItemFound in the TakeWhile clause
// That is what I'm wondering.

sourceList.Reverse()
    .TakeWhile(o => (o != limitItem) && !limitItemFound; limitItemFound = limitItemFound || (o == limitItem) )
    .FirstOrDefault(o => ...);

This would make the search inclusive of limitItem.

Answer 1

For LINQ to Objects (which takes delegates) then you can, yes - using a statement lambda:

sourceList.Reverse()
    .TakeWhile(o =>  { 
             ... fairly arbitrary code here
             return someValue;
         })
    .FirstOrDefault(o => ...);

I would strongly discourage you from doing this though. It will make it much harder to understand what's going on, because you're losing the declarative nature of idiomatic LINQ code.