Are lambda expressions/delegates in C# "pure", or can they be?
- by Bob
I recently asked about functional programs having no side effects, and learned what this means for making parallelized tasks trivial. Specifically, that "pure" functions make this trivial as they have no side effects.
I've also recently been looking into LINQ and lambda expressions as I've run across examples many times here on StackOverflow involving enumeration. That got me to wondering if parallelizing an enumeration or loop can be "easier" in C# now.
Are lambda expressions "pure" enough to pull off trivial parallelizing? Maybe it depends on what you're doing with the expression, but can they be pure enough? Would something like this be theoretically possible/trivial in C#?:
Break the loop into chunks
Run a thread to loop through each chunk
Run a function that does something with the value from the
current loop position of each thread
For instance, say I had a bunch of objects in a game loop (as I am developing a game and was thinking about the possibility of multiple threads) and had to do something with each of them every frame, would the above be trivial to pull off? Looking at IEnumerable it seems it only keeps track of the current position, so I'm not sure I could use the normal generic collections to break the enumeration into "chunks".
Sorry about this question. I used bullets above instead of pseudo-code because I don't even know enough to write pseudo-code off the top of my head. My .NET knowledge has been purely simple business stuff and I'm new to delegates and threads, etc. I mainly want to know if the above approach is good for pursuing, and if delegates/lambdas don't have to be worried about when it comes to their parallelization.
