All of these objects, when used as E-references, must be treated as immutable:
cl:string
cl:cons
cl:array
Symbols may be mutated, even though E-on-CL treats them as immutable atoms, as the mutable components of symbols are not exposed to the E system.
An e.elib:ref to an object must be treated equivalently to the object itself. This may be accomplished by dereference using ref-shorten, e-coerce, or e-coercef.
No distinctions may be made between objects that e.elib:equalizers consider equal.