[plt-scheme] What causes error: compile: bad syntax; function application is not allowed, because no #%app syntax transformer is bound in: (#%top-interaction . list-of-email)

Hi,

I'm getting an error;

. compile: bad syntax; function application is not allowed, because no
#%app syntax transformer is bound in: (#%top-interaction .
list-of-email)

What happens is;
1.  I run my (module language) program in drscheme,
2. It fails with an error (no sense pretending this doesn't happen a lot)
3. I type in the name of a variable I want to inspect
4. above error occurs.

I didn't get this error in 3xx, and I don't get it all the time, and
I'm having trouble working out what is causing it?
--
Welcome to DrScheme, version 4.0.1 [3m].
Language: Module custom.
. . car: expects argument of type <pair>; given false
> list-of-email
. compile: bad syntax; function application is not allowed, because no
#%app syntax transformer is bound in: (#%top-interaction .
list-of-email)
>
--

Cheers,

Stephen

--
Stephen De Gabrielle
s.degabrielle at cs.ucl.ac.uk
Telephone +44 (0)20 7679 0693 (x30693)
Mobile                  079 851 890 45
Project: Making Sense of Information (MaSI)
Work:http://www.uclic.ucl.ac.uk/annb/MaSI.html
Home:http://www.degabrielle.name/stephen


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