prolog-electric--dash
prolog-electric--dash is a compiled Lisp function in `prolog.el
'.
(prolog-electric--dash)
If `prolog-electric-dash-flag' is non-nil, insert the electric `-' construct.
that is, insert space (if appropriate), `-->' and newline if dash is pressed
at the end of a line that starts in the first column (i.e., DCG heads).