2.24 Internal-Definition Limiting: #%stratified-body
syntax
(#%stratified-body defn-or-expr ...)
Like (let () defn-or-expr ...) for an
internal-definition context sequence, except that an expression
is not allowed to precede a definition, and all definitions are
treated as referring to all other definitions (i.e., locations
for variables are all allocated first, like letrec and
unlike letrec-syntaxes+values).
The #%stratified-body form is useful for implementing syntactic forms or languages that supply a more limited kind of internal-definition context.