[racket] Simple Scheme Interpreter written in Drracket

From: Peter Breitsprecher (pkbreits at lakeheadu.ca)
Date: Tue Nov 9 15:27:08 EST 2010

I'd lie but no.. I was just trying to clarify what I was looking for.  I
gave a the code for one of the functions I had written, and then an example
of the input the user is giving below, and then tried to describe in more
detail what I needed help with...

On 9 November 2010 15:23, Shriram Krishnamurthi <sk at cs.brown.edu> wrote:

> Hi,
> That would not be considered an "example" for at least two reasons. Do you
> see why?
> On Nov 9, 2010 12:17 PM, "Peter Breitsprecher" <pkbreits at lakeheadu.ca>
> wrote:
> As an example, I want have most of the functions for Plus, Minus already
> written.
> Here is the code for it.
> (define (plus num1 num2)
> (+ num1 num2))
> That is childs stuff...  Here is where I am having the problem, and please
> keep in mind I am new to DrRacket...
> If my program accepts input such as
> (plus 13 5)
> I need to parse it so that I know what it is asking for.  If It is a left
> parent, then I need to move on, if it is a right parent, move on to the next
> character, once i get to the next character I can see it is an alphanumeric
> character, but then I need to somehow read the whole word, so that I can
> store that value in a variable so that I can read the next number.  If the
> numbers are single digits, it is easy, because they are only one charater
> each and read-char works perfect, but I need something like a read-word, or
> read-number and I can't seem to figure out how to do it.
> So really I need to know how do I read the words when there are characters
> present, and read the whole numbers when there is a number present.
> On 9 November 2010 15:00, John Clements <clements at brinckerhoff.org> wrote:
> >
> >
> > On Nov 9, 2010, a...
> --
> Kurt Breitsprecher
> (807) 474-9601
> pkbreits at lakeheadu.ca
> _________________________________________________
>  For list-related administrative tasks:
>  http://lists.racket-lang.org/listinfo/users

Kurt Breitsprecher
(807) 474-9601
pkbreits at lakeheadu.ca
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