Tidy up documentation associated with window groups.

* doc/lispref/windows.texi (Basic Windows): Add an @anchor for "Window
Groups".  Correct example function to `window-group-start'.
(Window Start and End, Textual scrolling): Point to the new anchor.  State
that (most of) the args in window group functions have the same meaning as for
the corresponding window primitives.

* doc/lispref/positions.texi (Screen Lines).  Same as above.

2 files changed, 27 insertions, 26 deletions

diff --git a/doc/lispref/positions.texi b/doc/lispref/positions.texi
index 090eb4598a8..9daf5cef059 100644
--- a/doc/lispref/positions.texi
+++ b/doc/lispref/positions.texi
@@ -575,14 +575,13 @@ the top line in the window numbered 0.
 @vindex move-to-window-group-line-function
 @defun move-to-window-group-line count
 This function is like @code{move-to-window-line}, except that when the
-selected window is a part of a group of windows (@pxref{Basic
-Windows}), @code{move-to-window-group-line} will move to a position
-with respect to the entire group, not just the single window.  This
+selected window is a part of a group of windows (@pxref{Window
+Group}), @code{move-to-window-group-line} will move to a position with
+respect to the entire group, not just the single window.  This
 condition holds when the buffer local variable
 @code{move-to-window-group-line-function} is set to a function.  In
 this case, @code{move-to-window-group-line} calls the function with
-the argument @var{count}, then returns its result.  The argument has
-the same meaning as in @code{move-to-window-line}.
+the argument @var{count}, then returns its result.
 @end defun
 
 @defun compute-motion from frompos to topos width offsets window
diff --git a/doc/lispref/windows.texi b/doc/lispref/windows.texi
index 45899588c32..0c0c1bce3b9 100644
--- a/doc/lispref/windows.texi
+++ b/doc/lispref/windows.texi
@@ -133,14 +133,14 @@ This function returns the selected window (which is always a live
 window).
 @end defun
 
-  Sometimes several windows collectively and cooperatively display a
-buffer, for example, under the management of Follow Mode, where the
-windows together display a bigger portion of the buffer than one
-window could alone.  It is often useful to consider such a @dfn{group
-of windows} as a single entity.  Several functions such as
-@code{window-start} (@pxref{Window Start and End}) allow you to do
-this by supplying, as an argument, one of the windows as a stand in
-for the whole group.
+@anchor{Window Group}Sometimes several windows collectively and
+cooperatively display a buffer, for example, under the management of
+Follow Mode (@pxref{Follow Mode,,, emacs}), where the windows together
+display a bigger portion of the buffer than one window could alone.
+It is often useful to consider such a @dfn{window group} as a single
+entity.  Several functions such as @code{window-group-start}
+(@pxref{Window Start and End}) allow you to do this by supplying, as
+an argument, one of the windows as a stand in for the whole group.
 
 @defun selected-window-group
 @vindex selected-window-group-function
@@ -3125,13 +3125,12 @@ position to change in response until after the next redisplay.
 @defun window-group-start &optional window
 @vindex window-group-start-function
 This function is like @code{window-start}, except that when
-@var{window} is a part of a group of windows (@pxref{Basic Windows}),
+@var{window} is a part of a group of windows (@pxref{Window Group}),
 @code{window-group-start} returns the start position of the entire
 group.  This condition holds when the buffer local variable
 @code{window-group-start-function} is set to a function.  In this
 case, @code{window-group-start} calls the function with the single
-argument @var{window}, then returns its result.  The argument to this
-function has the same meaning as in @code{window-start}.
+argument @var{window}, then returns its result.
 @end defun
 
 @cindex window end position
@@ -3163,13 +3162,13 @@ text will end if scrolling is not required.
 @vindex window-group-end-function
 @defun window-group-end window update
 This function is like @code{window-end}, except that when @var{window}
-is a part of a group of windows (@pxref{Basic Windows}),
+is a part of a group of windows (@pxref{Window Group}),
 @code{window-group-end} returns the end position of the entire group.
 This condition holds when the buffer local variable
 @code{window-group-end-function} is set to a function.  In this case,
 @code{window-group-end} calls the function with the two arguments
-@var{window} and @var{update}, then returns its result.  The arguments
-to this function have the same meaning as in @code{window-end}.
+@var{window} and @var{update}, then returns its result.  The argument
+@var{update} has the same meaning as in @code{window-end}.
 @end defun
 
 @defun set-window-start window position &optional noforce
@@ -3238,14 +3237,14 @@ position that works well with point, and thus @var{position} is not used.
 @vindex set-window-group-start-function
 @defun set-window-group-start window position &optional noforce
 This function is like @code{set-window-start}, except that when
-@var{window} is a part of a group of windows (@pxref{Basic Windows}),
+@var{window} is a part of a group of windows (@pxref{Window Group}),
 @code{set-window-group-start} sets the start position of the entire
 group.  This condition holds when the buffer local variable
 @code{set-window-group-start-function} is set to a function.  In this
 case, @code{set-window-group-start} calls the function with the three
 arguments @var{window}, @var{position}, and @var{noforce}, then
-returns its result.  The arguments in this function have the same
-meaning as in @code{set-window-start}.
+returns its result.  The arguments @var{position} and @var{noforce} in
+this function have the same meaning as in @code{set-window-start}.
 @end defun
 
 @defun pos-visible-in-window-p &optional position window partially
@@ -3292,14 +3291,16 @@ Here is an example:
 @vindex pos-visible-in-window-group-p-function
 @defun pos-visible-in-window-group-p &optional position window partially
 This function is like @code{pos-visible-in-window-p}, except that when
-@var{window} is a part of a group of windows (@pxref{Basic Windows}),
+@var{window} is a part of a group of windows (@pxref{Window Group}),
 @code{pos-visible-in-window-group-p} tests the visibility of @var{pos}
 in the entire group, not just in the single @var{window}.  This
 condition holds when the buffer local variable
 @code{pos-visible-in-window-group-p-function} is set to a function.
 In this case @code{pos-visible-in-window-group-p} calls the function
 with the three arguments @var{position}, @var{window}, and
-@var{partially}, then returns its result.
+@var{partially}, then returns its result.  The arguments
+@var{position} and @var{partially} have the same meaning as in
+@code{pos-visible-in-window-p}.
 @end defun
 
 @defun window-line-height &optional line window
@@ -3548,12 +3549,13 @@ a more convenient way to achieve this.
 @vindex recenter-group-function
 @defun recenter-group &optional count
 This function is like @code{recenter}, except that when the selected
-window is part of a group of windows (@pxref{Basic Windows}),
+window is part of a group of windows (@pxref{Window Group}),
 @code{recenter-group} scrolls the entire group.  This condition holds
 when the buffer local variable @code{recenter-group-function} is set
 to a function.  In this case, @code{recenter-group} calls the function
 with the argument @var{count}, then returns its result.  The argument
-has the same meaning as in @code{recenter}.
+@var{count} has the same meaning as in @code{recenter}, but with
+respect to the entire window group.
 @end defun
 
 @defopt recenter-redisplay