[plt-scheme] Re: Explanation of this piece of code?

From: -gary- (gary.dunne1 at gmail.com)
Date: Sat Apr 25 22:42:07 EDT 2009

Thank you Neil.

"get-person" is returning a list of people in a certain group/members
of a specific group.

I didn't write this section of code, which leads me back to my
original question, if anyone had an idea of what is going on in it.
As far as I can gather, the code is looping and calling a function
whose return value is going into "mod".  I'm still a little confused
by "let*", "map" and "filter".
Basically, I'm just trying to call this function "get-person", then
output this info.

> For one thing, you need a "," or ",@" in front of the "mod".  Look up
> "quasiquote" in the documentation, which is what that backquote
> character is shorthand for.

Thanks for pointing this out, this has explained a lot.

Also, thank you for tolerating (what I do realize are) very basic
questions.



On Apr 25, 9:58 pm, Neil Van Dyke <n... at neilvandyke.org> wrote:
> -gary- wrote at 04/25/2009 09:00 PM:
>
> > If possible, could you please tell me what is going on in this piece of code?
>
> It appears that "get-person" returns a list of lists.
>
> I could point out what look like stylistic problems with the code, but
> first you should say why "get-person" returns a list of lists.
>
> Also, if you wrote this code, yet need it explained, I suggest backing
> up.  Start DrScheme, type shorter expressions of the code, and see what
> they do.
>
> >     `(span
> >      ( mod    ))   ***
>
> > Also, where I marked "***" above, this was an attempt to print out the
> > returned values, I realize this is most lilkely incorrect, how would I
> > print out these values?
>
> For one thing, you need a "," or ",@" in front of the "mod".  Look up
> "quasiquote" in the documentation, which is what that backquote
> character is shorthand for.
>
> --http://www.neilvandyke.org/
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