Syntax:  ENTER LINE

  Enters a new comment line or text line.

  If the cursor is positioned within a comment (as defined in the
  current language) and wrapping is set for the buffer, then the new
  line will be a comment line otherwise, it will be a blank line.

  If the cursor is at the end of a line, the ENTER LINE command adds a
  new blank line following the current line.

  If the cursor is at the beginning of a line, this command adds a new
  blank line before the current line.

  If the cursor is positioned within a line, that line is split into
  two lines at the original cursor position.