> My understanding is that R5RS includes 'do' in the language, which
> is a primitive, iterative construct.
"do" is iterative but not primitive: it is defined in R5RS
using a high-level macro (now the only kind of macro), using
tail iteration.
The *primitive* constructs are application, "if", "set!",
"lambda", and variable reference.
-- John Cowan http://www.ccil.org/~cowan cowan@ccil.org You tollerday donsk? N. You tolkatiff scowegian? Nn. You spigotty anglease? Nnn. You phonio saxo? Nnnn. Clear all so! 'Tis a Jute.... (Finnegans Wake 16.5)