Display function body



I'm trying to display the definitions of functions/macros I've  
implemented earlier. How can I do that?

(%i1) rect ( x ) ::= if ( abs ( x ) < 1/2 ) then 1 else 0  $
(%i4) string ( rect ( x ) );   <-- should give: rect(x) ::= if abs(x)  
< 1/2 then 1 else 0
Maxima was unable to evaluate the predicate:   <-- gives
                1
abs(x) < -
                2
#0: rect(x=x)
-- an error.  Quitting.  To debug this try debugmode(true);


What I wanted to do in the first place was

(%i3) integrate ( rect ( x ) * %e ^ ( -%i * w * x ) / sqrt ( 2 * % 
pi ) );

This yielded the same error message.

Regards

Philipp