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2.25 Internal-Definition Limiting: #%stratified-body

(#%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.