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truth of (), etc...


I strongly agree with the following change to the truth value of ():

   Sections 3.2 (True and false), 4.1.5 (Conditionals),
   and 6.1 (Booleans).  It will be explicitly unspecified whether
   the empty list counts as true or as false in a conditional
   expression.

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We need peek-char; remember JAR's point that it should be possible to
write READ in Scheme.  The note in R3.95RS looks good.

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On macros,

  Chris Hanson deserves great credit for developing a macro facility
  along the lines envisioned at Snowbird, but the well-specified part
  of it does not seem to be sufficiently powerful.  I gather that the
  system itself is adequately powerful, provided we accept that "the
  implementation is the specification", but we certainly don't want to
  accept that.

Is there anything written that would explain the current situation in
more detail?

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Is there any support for the idea of giving internal definitions the
same semantics as top level definitions?  I have yet to hear a strong
argument as to why they should mean something different.  Maybe R4RS
should explain the decision it describes.

<BODY> --> (define <I> <EXP>) ... <SEQUENCE> ==>
  ((lambda (<I> ...)
     (set! <I> <EXP>)
     ...
     <SEQUENCE>)
   <UNDEFINED> ...)

John