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Re: [Scheme-reports] grammar of numbers

Alex Shinn scripsit:

> The grammar for complex numbers without a real part is quite explicitly
> making the sign mandatory, and this goes back to R4RS.  I don't know
> offhand what the rationale was - the only thing that comes to mind is
> symmetry with the fact that i by itself requires a sign to distinguish
> from the favored index variable.

I don't think there is a rationale.  Somewhere between R3RS and R4RS,
someone noticed that `+35i` was a reasonable alternative to `0+35i`,
(which was the only syntax allowed by R2RS and R3RS), so it was added.
Nobody proposed `35i`, so it didn't get in.

John Cowan      http://www.ccil.org/~cowan      cowan@x
Be yourself.  Especially do not feign a working knowledge of RDF where
no such knowledge exists.  Neither be cynical about RELAX NG; for in
the face of all aridity and disenchantment in the world of markup,
James Clark is as perennial as the grass.  --DeXiderata, Sean McGrath

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