SYS defines a number of routines for accessing system information:
Tests two objects for equality. If the arguments are of different type, it returns 'false'. If both objects are immutable, this is a recursive test on the arguments' attributes. If they are reference types, it returns 'true' if the arguments are the same object. It is a fatal error to call with external, closure, or void reference arguments.
Defines an arbitrary total order on objects. This never returns true if 'is_eq' would return true with the same arguments. It is a fatal error to call with external, closure, or void reference arguments.
Defines an arbitrary hash function. For reference arguments, this is a hash of the pointer; for immutable types, a recursive hash of all attributes. Hash values for two objects are guaranteed to be identical when 'is_eq' would return true, but the converse is not true.
Returns the concrete type of an object encoded as an 'INT'.
Returns a string representation associated with the integer. Useful for debugging in combination with 'type' above.
Explicitly deallocates an object. Sather is garbage collected and casual use of 'destroy' is discouraged. Sather implementations provide a way of detecting accesses to destroyed objects (a fatal error).