try-complete-lisp-symbol-partially

try-complete-lisp-symbol-partially is a compiled Lisp function in `hippie-exp.el'.

(try-complete-lisp-symbol-partially OLD)

Try to complete as an Emacs Lisp symbol, as many characters as unique.
The argument OLD has to be nil the first call of this function. It
returns t if a unique, possibly partial, completion is found, nil
otherwise.