I\'m wondering how the following is done in Rails 4 or if I just use the Rails 3 approach for using a lambda that can pass an argument the same way with 4 as I do with 3. >
Ruby has not deprecated the old style of lambda either, so if you feel more comfortable using that by all means go for it.
I don't personally like the stabby lambda's syntax myself but eventually they will probably become the norm so it doesn't hurt to get used to them.