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Document new features in constrain-to-field.
  Fix up some other entries.
  Remove entries for nonexistant functions.
This commit is contained in:
Miles Bader 2000-10-03 01:56:53 +00:00
parent a6d81c937b
commit 35627f726a
1 changed files with 29 additions and 32 deletions
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61
lispref/text.texi
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@ -3128,8 +3128,9 @@ buffer.
A field is a range of consecutive characters in the buffer that are
identified by having the same value (comparing with @code{eq}) of the
@code{field} property. This section describes special functions that
are available for operating on fields.
@code{field} property (either a text-property or an overlay property).
This section describes special functions that are available for
operating on fields.
You specify a field with a buffer position, @var{pos}. We think of
each field as containing a range of buffer positions, so the position
@ -3158,20 +3159,21 @@ value of point is used by default.
@tindex field-beginning
This function returns the beginning of the field specified by @var{pos}.
If @var{pos} is at the end of a field, and @var{escape-from-edge} is
non-@code{nil}, then the return value is always the beginning of the
field that @emph{ends} at @var{pos}, regardless of the stickiness of the
@code{field} properties around @var{pos}.
If @var{pos} is at the beginning of its field, and
@var{escape-from-edge} is non-@code{nil}, then the return value is
always the beginning of the preceding field that @emph{ends} at @var{pos},
regardless of the stickiness of the @code{field} properties around
@var{pos}.
@end defun
@defun field-end &optional pos escape-from-edge
@tindex field-end
This function returns the end of the field specified by @var{pos}.
If @var{pos} is at the beginning of a field, and @var{escape-from-edge}
is non-@code{nil}, then the return value is always the end of the field
that @emph{begins} at @var{pos}, regardless of the stickiness of the
@code{field} properties around @var{pos}.
If @var{pos} is at the end of its field, and @var{escape-from-edge} is
non-@code{nil}, then the return value is always the end of the following
field that @emph{begins} at @var{pos}, regardless of the stickiness of
the @code{field} properties around @var{pos}.
@end defun
@defun field-string &optional pos
@ -3191,23 +3193,7 @@ as a string, discarding text properties.
This function deletes the text of the field specified by @var{pos}.
@end defun
@deffn beginning-of-line-or-field &optional count
@tindex beginning-of-line-or-field
Like @code{beginning-of-line}, except that this function does not move
across a field boundary (@pxref{Fields}), unless it moves to another
line beyond the one that contains the field boundary. Therefore, if
@var{count} is zero, and point is initially at a field boundary, point
does not move.
@end deffn
@deffn end-of-line-or-field &optional count
@tindex end-of-line-or-field
Like @code{end-of-line}, except that this function does not move
across a field boundary (@pxref{Fields}), unless it moves to another
line beyond the one that contains the field boundary.
@end deffn
@defun constrain-to-field new-pos old-pos &optional escape-from-edge only-in-line
@defun constrain-to-field new-pos old-pos &optional escape-from-edge only-in-line inhibit-capture-property
@tindex constrain-to-field
This function ``constrains'' @var{new-pos} to the field that
@var{old-pos} belongs to---in other words, it returns the position
@ -3220,11 +3206,14 @@ If @var{old-pos} is at the boundary of two fields, then the acceptable
positions for @var{new-pos} depend on the value of the optional argument
@var{escape-from-edge}. If @var{escape-from-edge} is @code{nil}, then
@var{new-pos} is constrained to the field that has the same @code{field}
text-property that new characters inserted at @var{old-pos} would get.
(This depends on the stickiness of the @code{field} property for the
characters before and after @var{old-pos}.) If @var{escape-from-edge}
is non-@code{nil}, @var{new-pos} is constrained to the union of the two
adjacent fields.
property (either a text-property or an overlay property) that new
characters inserted at @var{old-pos} would get. (This depends on the
stickiness of the @code{field} property for the characters before and
after @var{old-pos}.) If @var{escape-from-edge} is non-@code{nil},
@var{new-pos} is constrained to the union of the two adjacent fields.
Additionally, if two fields are separated by another field with the
special value @code{boundary}, then any point within this special field
is also considered to be ``on the boundary.''
If the optional argument @var{only-in-line} is non-@code{nil}, and
constraining @var{new-pos} in the usual way would move it to a different
@ -3232,6 +3221,14 @@ line, @var{new-pos} is returned unconstrained. This used in commands
that move by line, such as @code{next-line} and
@code{beginning-of-line}, so that they respect field boundaries only in
the case where they can still move to the right line.
If the optional argument @var{inhibit-capture-property} is
non-@code{nil}, and @var{old-pos} has a non-@code{nil} property of that
name, then any field boundaries are ignored.
You can cause @code{constrain-to-field} to ignore all field boundaries
(and so never constrain anything) by binding the variable
@code{inhibit-field-text-motion} to a non-nil value.
@end defun
@node Not Intervals