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Re: [Scheme-reports] Formal - Internal syntax definitions vs a body with definitions being a letrec*

Jussi Piitulainen scripsit:

> I desire a clarification on how a body that begins with internal
> definitions can be equivalent to a letrec* when syntax definitions are
> valid wherever definitions are.

Formal Comment #414 filed.

The language in 5.2.2 now reads:

# An expanded \hyper{body} containing internal definitions
# (but not syntax definitions or record definitions) can always be
# converted into a completely equivalent {\cf letrec*} expression.

> Finally, I still have a related concern about <body>: the entry on
> lambda expressions does not tell the truth about <body> allowing
> internal definitions, yet several binding constructs refer to it as
> being authoritative about <body>:
> 4.1.4 Procedures (p. 12 bottom right)
> ... <body> should be a sequence of one or more expressions.
> [this does not allow internal definitions]

Technically this is a substantive change, but arguably it is an error in
R5RS.  In my suite of 45 Schemes, only Oaklisp (which treats all defines
as external) and UMB (which has a bug here) do not accept ((lambda (x)
(define y 32) (+ x y)) 45) as correct and returning 77.  Therefore,
I have treated this change as editorial, making it read:

#  \hyper{body} should be a sequence of zero or more definitions
# followed by one or more expressions.
> Finally finally, "body" is not an index entry (p. 77) and it should
> be. Probably it should point to 4.1.4 but, as noted above, that site
> does not tell the truth about <body>, or body, and maybe to 5.2.2,
> where I'm formally seeking clarification. Thank you for your
> attention.

Editorial ticket #415 filed.  This will be done before the next draft.

Since all these changes are editorial, I am closing this Formal Comment.
Please treat this as a formal response.

Not to perambulate                 John Cowan <cowan@x>
    the corridors                  http://www.ccil.org/~cowan
during the hours of repose
    in the boots of ascension.       --Sign in Austrian ski-resort hotel

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