analog of fundef for Maxima functions defined in lisp file



On June 18, 2011, Richard Fateman wrote:
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Incidentally, some common lisps already store the file name and location 
on the property list of the function name, as files are loaded.
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Is this true for GCL?
Allegro?

What would be an example of accessing such a 
plist relating file name and location of a given
function in a lisp session?

Ted