Proposal: Type checking for variables inside of methods

[denis-mueller]

If I understand the docs correctly, this gem allows me to enforce types for params of the constructor (initialize method) of an object. But if I'm not missing anything, it's currently not possible to enforce the type for a variable inside a method, except for manually doing something like

def foo(bar)
  raise 'bar must be an integer' unless Integer === bar
end

It would be amazing, if there was a concise syntax to

a) check if a variable matches a literal type. do nothing if it matches, but raise if it doesn't match
b) try to coerce a variable into a type. do nothing if it works, raise an error if it's not possible to coerce

here a few ideas I had

Literal.check(_Integer, bar)
Literal.cast(_Integer, bar)

_Integer!(bar) # to check if bar is an integer
_Integer_(bar) # to cast bar to an integer

Now my questions @joeldrapper

1. Was my understanding/assumption correct that the literal gem does not have this feature right now?
2. Would this functionality match the philosophy of the literal gem and would this be something you would want to have included in the gem?