## Callsite annotations on var parameters would decrease mistakes Possibly. The problem here is that of perception. In many languages, heap allocation through pointers is the only method of having objects, and passing them to a function gives the freedom to modify them. In Nim, things can be allocated on the stack, and those things need to be treated in the same way as things on the heap. ``` nimrod proc foo(input: ref T) = ... let a: ref T foo(a) # valid, this is Java-style var b: T foo(b) # also valid and equivalent ```