.call_method obj, x = obj.method(x) # ERR
.member obj = obj.member # ERR
.D2! = Class Dict! { Str: List!(Int) }
.D2!.
new!() = .D2! !{:}
insert!(ref! self, name, val) =
self::base.insert! name, ![val]
d = .D2!.new!()
d.insert! "aaa", 1 # OK
d.insert! "aaa", "bbb" # ERR
d.insert! 1, 1 # ERR