[racket] repl parsing question

Thanks, I understand it now.  Racket is not Scheme but if I were to strictly
follow the R6RS, then both should fail, since both characters and booleans
require delimiters.

On Tue, Feb 1, 2011 at 9:35 AM, Matthew Flatt <mflatt at cs.utah.edu> wrote:

> Different Scheme variants vary in whether `#t' and `#f' must be
> followed by a delimiter. R6RS, for example, requires a delimiter.
>
> Prior to version 5.0.2, Racket did not require a delimiter, but now it
> does (while `#true' and `#false' are also allowed as booleans).
>
> At Tue, 1 Feb 2011 08:59:04 -0600, qld3303 wrote:
> > Hello,
> > I'm a beginner trying to write a simple Scheme interpreter to help
> > understand Racket better.  I try to mimic the results from the repl as
> best
> > possible however in some cases I'm not sure how to reproduce them, this
> > being one such case.  It seems to imply that an identifier or something
> > other than a boolean could begin with #t but I'm not sure.  I tried this
> > using Guile and got the opposite results:
> > guile> (+ 3 1)#t+
> > 4
> > #t
> > #<primitive-generic +>
> > guile> (+ 3 1)#\t+
> > 4
> > ERROR: In procedure scm_lreadr:
> > ERROR: #<unknown port>:2:1: unknown character name t+
> > ABORT: (read-error)
> >
> > Currently, my naive repl will work for both characters and booleans but
> > perhaps it shouldn't?
> >
> > Thanks
> >
> > On Mon, Jan 31, 2011 at 9:13 PM, qld3303 <qld3303 at gmail.com> wrote:
> >
> > > I'm not clear as to why the following occurs:
> > >
> > > > (+ 3 1)#t+
> > > 4
> > > readline-input::183: read: bad syntax `#t+'
> > >
> > > > (+ 3 1)#\t+
> > > 4
> > > #\t
> > > #<procedure:+>
> > >
> > > Why doesn't it recognize that #t is a boolean value?
> > >
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