Readonly variables inside method scopes

[osamakawish]

Basically I'd like something like this, if it's feasible:

public void DoStuff() {
    readonly int len = Enumarable.Count()
}

I can't use Count() likely because I'm evaluating a method, and methods are dynamic. But I don't want the len variable to change throughout the scope of the method, and it would be nice to express that. Tested the above code and getting the error the modifier readonly is not valid for this item.

Issues

Main issue here is that it's just... really not essential of a feature, but more of a nice addition. Function scopes aren't that large that adding this feature would reduce any bugs, or even easily cause any.

[HaloFour]

See: #188