Ruby doesn't give error on keyword arguments that you can't refer to
You can't use keywords as names for normal arguments. For example all of these give a syntax error:
def foo(class); end def foo(def); end def foo(if); end # ... other keywords too
The reason is that there's no way to refer to these names because they are keywords.
However, we can use these names for keyword arguments. All of these work:
def foo(class: 1); end def foo(def: 1); end def foo(if: 1); end
But I think they should give a syntax error, because for example I can't refer to the argument "class" in the first line (same reason why the first snippet gives a syntax error).