.name / .-name

(.method receiver args...) (.-field receiver)

The sugar for .: a dotted name calls the method on the receiver, a .--dotted one reads the instance field. The receiver decides the path as everywhere in interop, so a string receiver takes the mapped core operation, and another String method calls the string as a String. .toString of any value that is no host object answers its str spelling, on every backend. A collection, keyword, symbol, ratio or atom has no host object either: its common clojure.lang/java.util methods (.count, .size, .isEmpty, .get, .nth, .valAt, .contains, .containsKey, .indexOf, .getName, .getNamespace, .numerator, .deref, ...) answer through the matching core function on every backend, a method its class lacks is refused in the oracle's words, and any other method is refused by name. A record, deftype or reify answers what its class has, on every backend: a protocol method its body implements calls it ((.m r)), and a zero-argument name that is a declared field reads it ((.a r)); an extend-type method, an undeclared name or a mutable field is refused in the oracle's words (No matching field found: q for class user.R). A name that is no protocol method and no field of a record or deftype the program defined is refused by name, as on a collection. Anything else runs on the interpreter and the JVM only -- the wasm backends reject java:.