eintr: Void Function
1.7.1 Error Message for a Symbol Without a Function
---------------------------------------------------
When we evaluated ‘fill-column’ to find its value as a variable, we did
not place parentheses around the word. This is because we did not
intend to use it as a function name.
If ‘fill-column’ were the first or only element of a list, the Lisp
interpreter would attempt to find the function definition attached to
it. But ‘fill-column’ has no function definition. Try evaluating this:
(fill-column)
You will create a ‘*Backtrace*’ buffer that says:
---------- Buffer: *Backtrace* ----------
Debugger entered--Lisp error: (void-function fill-column)
(fill-column)
eval((fill-column))
eval-last-sexp-1(nil)
eval-last-sexp(nil)
call-interactively(eval-last-sexp)
---------- Buffer: *Backtrace* ----------
(Remember, to quit the debugger and make the debugger window go away,
type ‘q’ in the ‘*Backtrace*’ buffer.)
Info Catalog
eintr: fill-column Example
eintr: Variables
eintr: Void Variable