Info Catalog elisp: Buffer End Motion elisp: Motion elisp: Screen Lines

elisp: Text Lines

 
 29.2.4 Motion by Text Lines
 ---------------------------
 
 Text lines are portions of the buffer delimited by newline characters,
 which are regarded as part of the previous line.  The first text line
 begins at the beginning of the buffer, and the last text line ends at
 the end of the buffer whether or not the last character is a newline.
 The division of the buffer into text lines is not affected by the width
 of the window, by line continuation in display, or by how tabs and
 control characters are displayed.
 
  -- Command: beginning-of-line &optional count
      This function moves point to the beginning of the current line.
      With an argument COUNT not ‘nil’ or 1, it moves forward COUNT−1
      lines and then to the beginning of the line.
 
      Fields::) unless doing so would move beyond there to a different
      line; therefore, if COUNT is ‘nil’ or 1, and point starts at a
      field boundary, point does not move.  To ignore field boundaries,
      either bind ‘inhibit-field-text-motion’ to ‘t’, or use the
      ‘forward-line’ function instead.  For instance, ‘(forward-line 0)’
      does the same thing as ‘(beginning-of-line)’, except that it
      ignores field boundaries.
 
      If this function reaches the end of the buffer (or of the
      accessible portion, if narrowing is in effect), it positions point
      there.  No error is signaled.
 
  -- Function: line-beginning-position &optional count
      Return the position that ‘(beginning-of-line COUNT)’ would move to.
 
  -- Command: end-of-line &optional count
      This function moves point to the end of the current line.  With an
      argument COUNT not ‘nil’ or 1, it moves forward COUNT−1 lines and
      then to the end of the line.
 
      Fields::) unless doing so would move beyond there to a different
      line; therefore, if COUNT is ‘nil’ or 1, and point starts at a
      field boundary, point does not move.  To ignore field boundaries,
      bind ‘inhibit-field-text-motion’ to ‘t’.
 
      If this function reaches the end of the buffer (or of the
      accessible portion, if narrowing is in effect), it positions point
      there.  No error is signaled.
 
  -- Function: line-end-position &optional count
      Return the position that ‘(end-of-line COUNT)’ would move to.
 
  -- Command: forward-line &optional count
      This function moves point forward COUNT lines, to the beginning of
      the line following that.  If COUNT is negative, it moves point
      −COUNT lines backward, to the beginning of a line preceding that.
      If COUNT is zero, it moves point to the beginning of the current
      line.  If COUNT is ‘nil’, that means 1.
 
      If ‘forward-line’ encounters the beginning or end of the buffer (or
      of the accessible portion) before finding that many lines, it sets
      point there.  No error is signaled.
 
      ‘forward-line’ returns the difference between COUNT and the number
      of lines actually moved.  If you attempt to move down five lines
      from the beginning of a buffer that has only three lines, point
      stops at the end of the last line, and the value will be 2.  As an
      explicit exception, if the last accessible line is non-empty, but
      has no newline (e.g., if the buffer ends without a newline), the
      function sets point to the end of that line, and the value returned
      by the function counts that line as one line successfully moved.
 
      In an interactive call, COUNT is the numeric prefix argument.
 
  -- Function: count-lines start end
      This function returns the number of lines between the positions
      START and END in the current buffer.  If START and END are equal,
      then it returns 0.  Otherwise it returns at least 1, even if START
      and END are on the same line.  This is because the text between
      them, considered in isolation, must contain at least one line
      unless it is empty.
 
  -- Command: count-words start end
      This function returns the number of words between the positions
      START and END in the current buffer.
 
      This function can also be called interactively.  In that case, it
      prints a message reporting the number of lines, words, and
      characters in the buffer, or in the region if the region is active.
 
  -- Function: line-number-at-pos &optional pos
      This function returns the line number in the current buffer
      corresponding to the buffer position POS.  If POS is ‘nil’ or
      omitted, the current buffer position is used.
 
    Also see the functions ‘bolp’ and ‘eolp’ in Near Point.
 These functions do not move point, but test whether it is already at the
 beginning or end of a line.
 

Info Catalog elisp: Buffer End Motion elisp: Motion elisp: Screen Lines