[plt-scheme] Re: send-mail-message
At Wed, 22 Apr 2009 20:09:18 +0200, Thomas Chust wrote:
> 2009-04-22 -gary- <gary.dunne1 at gmail.com>:
> > [...]
> > "Your application raised an exception with the message:
> >
> > procedure application: expected procedure, given: "test at site.com" (no
> > arguments)"
> > [...]
>
> Hello Gary,
>
> your code contains the subexpression ("test at site.com") which is, like
> any list,
Clarification: it's not a list. The expression
("test at site.com")
is a function call, just like
(string-append "x" "y")
In the latter case, `string-append' is in the position of the function
expression --- which is good, because `string-append' is bound to a
function.
In the former, `"test at site.com"' is the function position --- which is
bad, because a string isn't a function.
The intent was presumably
(list "test at site.com")
to create a list that contains the string "test at site.com".
[I know that calling an application expression a "list" comes from the
Lisp way of thinking about how code is represented. If you want to
talk about the representation of an expression, though, I suggest
calling it "an address inside your computer's memory", because that's
how it's *actually* represented. :) ]