Info Catalog elisp: Positions elisp: Motion

elisp: Point

 
 29.1 Point
 ==========
 
 “Point” is a special buffer position used by many editing commands,
 including the self-inserting typed characters and text insertion
 functions.  Other commands move point through the text to allow editing
 and insertion at different places.
 
    Like other positions, point designates a place between two characters
 (or before the first character, or after the last character), rather
 than a particular character.  Usually terminals display the cursor over
 the character that immediately follows point; point is actually before
 the character on which the cursor sits.
 
    The value of point is a number no less than 1, and no greater than
 the buffer size plus 1.  If narrowing is in effect (Narrowing),
 then point is constrained to fall within the accessible portion of the
 buffer (possibly at one end of it).
 
    Each buffer has its own value of point, which is independent of the
 value of point in other buffers.  Each window also has a value of point,
 which is independent of the value of point in other windows on the same
 buffer.  This is why point can have different values in various windows
 that display the same buffer.  When a buffer appears in only one window,
 the buffer’s point and the window’s point normally have the same value,
 so the distinction is rarely important.  Window Point, for more
 details.
 
  -- Function: point
      This function returns the value of point in the current buffer, as
      an integer.
 
           (point)
                ⇒ 175
 
  -- Function: point-min
      This function returns the minimum accessible value of point in the
      current buffer.  This is normally 1, but if narrowing is in effect,
      it is the position of the start of the region that you narrowed to.
      (Narrowing.)
 
  -- Function: point-max
      This function returns the maximum accessible value of point in the
      current buffer.  This is ‘(1+ (buffer-size))’, unless narrowing is
      in effect, in which case it is the position of the end of the
      region that you narrowed to.  (Narrowing.)
 
  -- Function: buffer-end flag
      This function returns ‘(point-max)’ if FLAG is greater than 0,
      ‘(point-min)’ otherwise.  The argument FLAG must be a number.
 
  -- Function: buffer-size &optional buffer
      This function returns the total number of characters in the current
      buffer.  In the absence of any narrowing (Narrowing),
      ‘point-max’ returns a value one larger than this.
 
      If you specify a buffer, BUFFER, then the value is the size of
      BUFFER.
 
           (buffer-size)
                ⇒ 35
           (point-max)
                ⇒ 36
 

Info Catalog elisp: Positions elisp: Motion