Roughly equivalent as in they have very similar object model and each construct is trivial to convert into the other. each is just a fancy for with new scope, blocks can be replaced with local functions, etc. They don't have anything that's not a trivial transform away (like for example: tail calls, callcc, macros, compile time transformations, ...).

I mean, you may prefer one of these:

    foo.each { |i| ... }
    for i in foo: ...

but after fixing up the scope issues, they're the same thing.