[racket] repl parsing question

You'll want to read http://docs.racket-lang.org/reference/reader.html
In particular, section 12.6.4, "A #true, #t, #T followed by a
delimiter is the input syntax for the boolean constant 'true'.
Section 12.6.4 talks about what can be used as a delimiter.  Your
example fails because + is not a delimiter that the reader can use to
detect the end of the boolean.

Justin

On Tue, Feb 1, 2011 at 9:59 AM, qld3303 <qld3303 at gmail.com> 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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