[racket-dev] Please help me to fix the code

Hi Matthias,

The problem is not on the internet.   Since I am a beginner, I need to read
more.  If at last I cannot figure it out, I'll email you the requirements.

Thanks a lot.

On Tue, May 31, 2011 at 9:04 AM, Matthias Felleisen <matthias at ccs.neu.edu>wrote:

>
> Yingjian, if you point us to the web page with the problems, we might be
> able to help you more effectively.
>
>
>
>
>   On May 31, 2011, at 12:01 PM, Yingjian Ma wrote:
>
>   Hi Marijn,
>
> I am new to Racket.  I did not expect that output is
> "#<procedure:...uments...".  It is like an error message to me.
>
> Because the restrictions on this function (and on others), I need to study
> more about Racket to go further.  I also need to code a function to remove
> the duplicates from a list.  There is a such function in Racket but I cannot
> use it.
>
> On Tue, May 31, 2011 at 1:03 AM, Marijn <hkBst at gentoo.org> wrote:
>
>> -----BEGIN PGP SIGNED MESSAGE-----
>> Hash: SHA1
>>
>> Hi Yingjian,
>>
>> On 05/31/11 01:17, Yingjian Ma wrote:
>> > Hi All,
>> >
>> > I wrote a piece of code to count the occurrance of a letter in a list.
>>  But
>> > it gave me an error saying "#<procedure:...uments..."
>>
>> What makes you think it's an error?
>>
>> > The code is below:
>> >
>> > (define (count-matches s l)
>> >       (cond
>> >      [(empty? l) 0]
>> >      [(equal? s (first l)) (lambda (i)(+ i 1))]
>> >      [else (count-matches s (rest l))]))
>>
>> Part of this code reads:
>>
>> compare s to the first element of list l and if they are equal return a
>> function that returns its argument plus one (and forget about the rest
>> of the list).
>>
>> Marijn
>>
>> -----BEGIN PGP SIGNATURE-----
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>> iEYEARECAAYFAk3koL8ACgkQp/VmCx0OL2ztFwCfUG1WrfbagBXTp7F9prAvvaL8
>> sycAoJWBleSTJ/eE2CExwx1zt71Z1Lks
>> =e+cf
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>
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