HaloO, John M. Dlugosz wrote:
Yes. How is a snapshot different from the object?
My interpretation is that === is an equivalence relation on a WHICH set and eqv is an equivalence relation on a WHAT set. A "mutable value" is an element of a (n>1):1 mapping of a subset of WHAT to a single WHICH. A 1:1 mapping is an "immutable value". A 1:(m>1) mapping has no funny name. Neither has a n:m mapping. IOW, a value is a subset of the cartesian product of the WHAT and WHICH sets. A snapshot of a value is picking one element of that set. For == the WHAT is Num and for eq it is Str. Both map 1:1 to their respective WHICH sets. The =:= checks binding of names so it is an equivalence relation on a set of names. But I'm unsure if such a set is denoted with WHO or VAR. But I tend to think it's the latter. Regards, TSa. -- "The unavoidable price of reliability is simplicity" -- C.A.R. Hoare "Simplicity does not precede complexity, but follows it." -- A.J. Perlis 1 + 2 + 3 + 4 + ... = -1/12 -- Srinivasa Ramanujan