[plt-scheme] Are booleans s-expressions?

On Mar 19, 2010, at 10:18 AM, David Van Horn wrote:

> On 3/19/10 6:52 AM, Matthias Felleisen wrote:
>>
>> That bug was fixed a week ago. Next release is coming out soon.
>
> If you understand S-expressions as anything you can write down with  
> quote notation, then Booleans are not S-expressions in ISL.  So what  
> does fixing the bug mean?  Can you write #t and #f for Booleans now?


No. Instead we don't teach about ' in the way older Lispers did :-)




>
> David
>
>
>> On Mar 19, 2010, at 12:31 AM, Stephen Chang wrote:
>>
>>> I'm using PLT scheme 4.2.3 on windows xp. I'm using the intermediate
>>> language with lambda and the 2htdp/universe teachpack.
>>>
>>> The documentation says that booleans are s-expressions but the sexp?
>>> function doesnt seem to recognize that. Am I using it wrong?
>>>
>>>> (sexp? true)
>>> false
>>>> (sexp? false)
>>> false
>>>
>>> http://download.plt-scheme.org/doc/4.2.3/html/teachpack/2htdpuniverse.html#%28tech._s._expression%29
>>>
>>> S-expression An S-expression is roughly a nested list of basic data;
>>> to be precise, an S-expression is one of:
>>>
>>>    *     a string,
>>>    *     a symbol,
>>>    *     a number,
>>>    *     a boolean,
>>>    *     a char, or
>>>    *     a list of S-expressions.
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>>
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>