formatter control-string → function

control-string — a format string; not evaluated.

function — a function.

Returns a function which has behavior equivalent to:

#'(lambda (*standard-output* &rest arguments) 
    (apply #'format t control-string arguments) 
    arguments-tail)

where arguments-tail is either the tail of arguments which has as its car the argument that would be processed next if there were more format directives in the control-string, or else nil if no more arguments follow the most recently processed argument.

(funcall (formatter "~&~A~A") *standard-output* 'a 'b 'c) 
⊳ AB 
→ (C) 

(format t (formatter "~&~A~A") 'a 'b 'c) 
⊳ AB 
→ NIL

Might signal an error (at macro expansion time or at run time) if the argument is not a valid format string.

format