'\"
'\" Copyright (c) 1992 The Regents of the University of California.
'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\" 
.TH text n 8.5 Tk "Tk Built-In Commands"
.so man.macros
.BS
'\" Note:  do not modify the .SH NAME line immediately below!
.SH NAME
text, tk_textCopy, tk_textCut, tk_textPaste \- Create and manipulate text widgets
.SH SYNOPSIS
.nf
\fBtext\fR \fIpathName \fR?\fIoptions\fR?
\fBtk_textCopy\fR \fIpathName\fR
\fBtk_textCut\fR \fIpathName\fR
\fBtk_textPaste\fR \fIpathName\fR
.SO
\-background	\-highlightthickness	\-relief
\-borderwidth	\-insertbackground	\-selectbackground
\-cursor	\-insertborderwidth	\-selectborderwidth
\-exportselection	\-insertofftime	\-selectforeground
\-font	\-insertontime	\-setgrid
\-foreground	\-insertwidth	\-takefocus
\-highlightbackground	\-padx	\-xscrollcommand
\-highlightcolor	\-pady	\-yscrollcommand
.SE
.SH "WIDGET-SPECIFIC OPTIONS"
.OP \-autoseparators autoSeparators AutoSeparators
Specifies a boolean that says whether separators are automatically
inserted in the undo stack. Only meaningful when the \fB\-undo\fR
option is true.
.OP \-blockcursor blockCursor BlockCursor
.VS 8.5
Specifies a boolean that says whether the blinking insertion cursor
should be drawn as a character-sized rectangular block.  If false
(the default) a thin vertical line is used for the insertion cursor.
.VE 8.5
.OP \-endline endLine EndLine
.VS 8.5
Specifies an integer line index representing the line of the underlying
textual data store that should be just after the last line contained in
the widget.
This allows a text widget to reflect only a portion of a larger piece
of text.   Instead of an integer, the empty string can be provided to
this configuration option, which will configure the widget to end
at the very last line in the textual data store.
.VE 8.5
.OP \-height height Height
Specifies the desired height for the window, in units of characters
in the font given by the \fB\-font\fR option.
Must be at least one.
.OP \-inactiveselectbackground inactiveSelectBackground Foreground
.VS 8.5
Specifies the colour to use for the selection (the \fBsel\fR tag) when
the window does not have the input focus.  If empty, \fB{}\fR, then no
selection is shown when the window does not have the focus.
.VE 8.5
.OP \-maxundo maxUndo MaxUndo
Specifies the maximum number of compound undo actions on the undo
stack. A zero or a negative value imply an unlimited undo stack.
.OP \-spacing1 spacing1 Spacing1
Requests additional space above each text line in the widget,
using any of the standard forms for screen distances.
If a line wraps, this option only applies to the first line
on the display.
This option may be overridden with \fB\-spacing1\fR options in
tags.
.OP \-spacing2 spacing2 Spacing2
For lines that wrap (so that they cover more than one line on the
display) this option specifies additional space to provide between
the display lines that represent a single line of text.
The value may have any of the standard forms for screen distances.
This option may be overridden with \fB\-spacing2\fR options in
tags.
.OP \-spacing3 spacing3 Spacing3
Requests additional space below each text line in the widget,
using any of the standard forms for screen distances.
If a line wraps, this option only applies to the last line
on the display.
This option may be overridden with \fB\-spacing3\fR options in
tags.
.OP \-startline startLine StartLine
.VS 8.5
Specifies an integer line index representing the first line of the
underlying textual data store that should be contained in the widget.
This allows a text widget to reflect only a portion of a larger piece
of text.  Instead of an integer, the empty string can be provided to
this configuration option, which will configure the widget to start
at the very first line in the textual data store.
.VE 8.5
.OP \-state state State
Specifies one of two states for the text:  \fBnormal\fR or \fBdisabled\fR.
If the text is disabled then characters may not be inserted or deleted
and no insertion cursor will be displayed, even if the input focus is
in the widget.
.OP \-tabs tabs Tabs
Specifies a set of tab stops for the window.  The option's value consists
of a list of screen distances giving the positions of the tab stops,
each of which is a distance relative to the left edge of the widget
(excluding borders, padding, etc).  Each
position may optionally be followed in the next list element
by one of the keywords \fBleft\fR, \fBright\fR, \fBcenter\fR,
or \fBnumeric\fR, which specifies how to justify
text relative to the tab stop.  \fBLeft\fR is the default; it causes
the text following the tab character to be positioned with its left edge
at the tab position.  \fBRight\fR means that the right edge of the text
following the tab character is positioned at the tab position, and
\fBcenter\fR means that the text is centered at the tab position.
\fBNumeric\fR means that the decimal point in the text is positioned
at the tab position;  if there is no decimal point then the least
significant digit of the number is positioned just to the left of the
tab position;  if there is no number in the text then the text is
right-justified at the tab position.
For example,
.QW "\fB\-tabs {2c left 4c 6c center}\fR"
creates three tab stops at two-centimeter intervals;  the first two use left
justification and the third uses center justification.
.RS
.PP
If the list of tab stops does not have enough elements to cover all
of the tabs in a text line, then Tk extrapolates new tab stops using
the spacing and alignment from the last tab stop in the list.  Tab
distances must be strictly positive, and must always increase from one
tab stop to the next (if not, an error is thrown).
The value of the \fBtabs\fR option may be overridden by \fB\-tabs\fR
options in tags.
.PP
If no \fB\-tabs\fR option is specified, or if it is specified as
an empty list, then Tk uses default tabs spaced every eight
(average size) characters.  To achieve a different standard spacing,
for example every 4 characters, simply configure the widget with
.QW "\fB\-tabs \N'34'[expr {4 * [font measure $font 0]}] left\N'34' \-tabstyle wordprocessor\fR" .
.RE
.OP \-tabstyle tabStyle TabStyle
Specifies how to interpret the relationship between tab stops on a line
and tabs in the text of that line.  The value must be \fBtabular\fR (the
default) or \fBwordprocessor\fR. Note that tabs are interpreted as they
are encountered in the text.  If the tab style is \fBtabular\fR then the
\fIn\fR'th tab character in the line's text will be associated with
the \fIn\fR'th
tab stop defined for that line.  If the tab character's x coordinate
falls to the right of the \fIn\fR'th tab stop, then a gap of a single space
will be inserted as a fallback.  If the tab style is \fBwordprocessor\fR
then any tab character being laid out will use (and be defined by) the
first tab stop to the right of the preceding characters already laid out
on that line.  The value of the \fBtabstyle\fR option may be overridden
by \fB\-tabstyle\fR options in tags.
.OP \-undo undo Undo
Specifies a boolean that says whether the undo mechanism is active or
not.
.OP \-width width Width
Specifies the desired width for the window in units of characters
in the font given by the \fB\-font\fR option.
If the font does not have a uniform width then the width of the character
.QW 0
is used in translating from character units to screen units.
.OP \-wrap wrap Wrap
Specifies how to handle lines in the text that are too long to be
displayed in a single line of the text's window.
The value must be \fBnone\fR or \fBchar\fR or \fBword\fR.
A wrap mode of \fBnone\fR means that each line of text appears as
exactly one line on the screen;  extra characters that do not fit
on the screen are not displayed.
In the other modes each line of text will be broken up into several
screen lines if necessary to keep all the characters visible.
In \fBchar\fR mode a screen line break may occur after any character;
in \fBword\fR mode a line break will only be made at word boundaries.
.BE

.SH DESCRIPTION
.PP
The \fBtext\fR command creates a new window (given by the
\fIpathName\fR argument) and makes it into a text widget.
Additional
options, described above, may be specified on the command line
or in the option database
to configure aspects of the text such as its default background color
and relief.  The \fBtext\fR command returns the
path name of the new window.
.PP
A text widget displays one or more lines of text and allows that
text to be edited.
Text widgets support four different kinds of annotations on the
text, called tags, marks, embedded windows or embedded images.
Tags allow different portions of the text
to be displayed with different fonts and colors.
In addition, Tcl commands can be associated with tags so
that scripts are invoked when particular actions such as keystrokes
and mouse button presses occur in particular ranges of the text.
See \fBTAGS\fR below for more details.
.PP
The second form of annotation consists of floating markers in the text
called
.QW marks .
Marks are used to keep track of various interesting positions in the
text as it is edited.
See \fBMARKS\fR below for more details.
.PP
The third form of annotation allows arbitrary windows to be
embedded in a text widget.
See \fBEMBEDDED WINDOWS\fR below for more details.
.PP
The fourth form of annotation allows Tk images to be embedded in a text
widget.
See \fBEMBEDDED IMAGES\fR below for more details.
.PP
The text widget also has a built-in undo/redo mechanism.
See \fBTHE UNDO MECHANISM\fR below for more details.
.PP
.VS 8.5
The text widget allows for the creation of peer widgets.  These are
other text widgets which share the same underlying data (text, marks,
tags, images, etc).  See \fBPEER WIDGETS\fR below for more details.
.VE 8.5
.SH INDICES
.PP
Many of the widget commands for texts take one or more indices
as arguments.
An index is a string used to indicate a particular place within
a text, such as a place to insert characters or one endpoint of a
range of characters to delete.
Indices have the syntax
.CS
\fIbase modifier modifier modifier ...\fR
.CE
Where \fIbase\fR gives a starting point and the \fImodifier\fRs
adjust the index from the starting point (e.g. move forward or
backward one character).  Every index must contain a \fIbase\fR,
but the \fImodifier\fRs are optional.
.VS 8.5
Most modifiers (as documented below) allow
an optional submodifier.  Valid submodifiers are \fBany\fR
and \fBdisplay\fR. If the submodifier is abbreviated, then it must be
followed by whitespace, but otherwise there need be no space between the
submodifier and the following \fImodifier\fR.  Typically the \fBdisplay\fR
submodifier adjusts the meaning of the following \fImodifier\fR to make
it refer to visual or non-elided units rather than logical units, but
this is explained for each relevant case below.  Lastly, where \fIcount\fR
is used as part of a modifier, it can be positive or negative, so
.QW "\fIbase\fR \- \-3 lines"
is perfectly valid (and equivalent to
.QW "\fIbase\fR +3lines" ).
.VE 8.5
.PP
The \fIbase\fR for an index must have one of the following forms:
.TP 12
\fIline\fB.\fIchar\fR
Indicates \fIchar\fR'th character on line \fIline\fR.
Lines are numbered from 1 for consistency with other UNIX programs
that use this numbering scheme.
Within a line, characters are numbered from 0.
If \fIchar\fR is \fBend\fR then it refers to the newline character
that ends the line.
.TP 12
\fB@\fIx\fB,\fIy\fR
Indicates the character that covers the pixel whose x and y coordinates
within the text's window are \fIx\fR and \fIy\fR.
.TP 12
\fBend\fR
Indicates the end of the text (the character just after the last
newline).
.TP 12
\fImark\fR
Indicates the character just after the mark whose name is \fImark\fR.
.TP 12
\fItag\fB.first\fR
Indicates the first character in the text that has been tagged with
\fItag\fR.
This form generates an error if no characters are currently tagged
with \fItag\fR.
.TP 12
\fItag\fB.last\fR
Indicates the character just after the last one in the text that has
been tagged with \fItag\fR.
This form generates an error if no characters are currently tagged
with \fItag\fR.
.TP 12
\fIpathName\fR
Indicates the position of the embedded window whose name is
\fIpathName\fR.
This form generates an error if there is no embedded window
by the given name.
.TP 12
\fIimageName\fR
Indicates the position of the embedded image whose name is
\fIimageName\fR.
This form generates an error if there is no embedded image
by the given name.
.PP
If the \fIbase\fR could match more than one of the above forms, such
as a \fImark\fR and \fIimageName\fR both having the same value, then
the form earlier in the above list takes precedence.
If modifiers follow the base index, each one of them must have one
of the forms listed below.  Keywords such as \fBchars\fR and \fBwordend\fR
may be abbreviated as long as the abbreviation is unambiguous.
.TP
\fB+ \fIcount\fR ?\fIsubmodifier\fR? \fBchars\fR
.VS 8.5
Adjust the index forward by \fIcount\fR characters, moving to later lines
in the text if necessary.  If there are fewer than \fIcount\fR characters
in the text after the current index, then set the index to the last index
in the text.  Spaces on either side of \fIcount\fR are optional.  If the
\fBdisplay\fR submodifier is given, elided characters are skipped over
without being counted.  If \fBany\fR is given, then all characters are
counted.  For historical reasons, if neither modifier is given then the
count actually takes place in units of index positions (see \fBindices\fR
for details).  This behaviour may be changed in a future major release,
so if you need an index count, you are encouraged to use \fBindices\fR
instead wherever possible.
.VE 8.5
.TP
\fB\- \fIcount\fR ?\fIsubmodifier\fR? \fBchars\fR
Adjust the index backward by \fIcount\fR characters, moving to earlier
lines in the text if necessary.  If there are fewer than \fIcount\fR
characters in the text before the current index, then set the index to
.VS 8.5
the first index in the text (1.0).  Spaces on either side of \fIcount\fR
are optional.  If the \fBdisplay\fR submodifier is given, elided
characters are skipped over without being counted.  If \fBany\fR is
given, then all characters are counted.  For historical reasons, if
neither modifier is given then the count actually takes place in units of
index positions (see \fBindices\fR for details).  This behaviour may be
changed in a future major release, so if you need an index count, you are
encouraged to use \fBindices\fR instead wherever possible.
.VE 8.5
.TP
\fB+ \fIcount\fR ?\fIsubmodifier\fR? \fBindices\fR
.VS 8.5
Adjust the index forward by \fIcount\fR index positions, moving to later
lines in the text if necessary.  If there are fewer than \fIcount\fR
index positions in the text after the current index, then set the index
to the last index position in the text.  Spaces on either side of
\fIcount\fR are optional.  Note that an index position is either a single
character or a single embedded image or embedded window.  If the
\fBdisplay\fR submodifier is given, elided indices are skipped over
without being counted.  If \fBany\fR is given, then all indices are
counted; this is also the default behaviour if no modifier is given.
.VE 8.5
.TP
\fB\- \fIcount\fR ?\fIsubmodifier\fR? \fBindices\fR
.VS 8.5
Adjust the index backward by \fIcount\fR index positions, moving to
earlier lines in the text if necessary.  If there are fewer than
\fIcount\fR index positions in the text before the current index, then
set the index to the first index position (1.0) in the text.  Spaces on
either side of \fIcount\fR are optional.  If the \fBdisplay\fR
submodifier is given, elided indices are skipped over without being
counted.  If \fBany\fR is given, then all indices are counted; this is
also the default behaviour if no modifier is given.
.VE 8.5
.TP
\fB+ \fIcount\fR ?\fIsubmodifier\fR? \fBlines\fR
.VS 8.5
Adjust the index forward by \fIcount\fR lines, retaining the same
character position within the line.  If there are fewer than \fIcount\fR
lines after the line containing the current index, then set the index to
refer to the same character position on the last line of the text.  Then,
if the line is not long enough to contain a character at the indicated
character position, adjust the character position to refer to the last
character of the line (the newline).  Spaces on either side of
\fIcount\fR are optional.  If the \fBdisplay\fR submodifier is given,
then each visual display line is counted separately.  Otherwise, if
\fBany\fR (or no modifier) is given, then each logical line (no matter
how many times it is visually wrapped) counts just once.  If the relevant
lines are not wrapped, then these two methods of counting are equivalent.
.VE 8.5
.TP
\fB\- \fIcount\fR ?\fIsubmodifier\fR? \fBlines\fR
.VS 8.5
Adjust the index backward by \fIcount\fR logical lines, retaining the
same character position within the line.  If there are fewer than
\fIcount\fR lines before the line containing the current index, then set
the index to refer to the same character position on the first line of
the text.  Then, if the line is not long enough to contain a character at
the indicated character position, adjust the character position to refer
to the last character of the line (the newline).  Spaces on either side
of \fIcount\fR are optional.  If the \fBdisplay\fR submodifier is given,
then each visual display line is counted separately.  Otherwise, if
\fBany\fR (or no modifier) is given, then each logical line (no matter
how many times it is visually wrapped) counts just once.  If the relevant
lines are not wrapped, then these two methods of counting are equivalent.
.VE 8.5
.TP
?\fIsubmodifier\fR? \fBlinestart\fR
.VS 8.5
Adjust the index to refer to the first index on the line.  If the
\fBdisplay\fR submodifier is given, this is the first index on the
display line, otherwise on the logical line.
.VE 8.5
.TP
?\fIsubmodifier\fR? \fBlineend\fR
.VS 8.5
Adjust the index to refer to the last index on the line (the
newline).  If the \fBdisplay\fR submodifier is given, this is the last
index on the display line, otherwise on the logical line.
.VE 8.5
.TP
?\fIsubmodifier\fR? \fBwordstart\fR
.VS 8.5
Adjust the index to refer to the first character of the word containing
the current index.  A word consists of any number of adjacent characters
that are letters, digits, or underscores, or a single character that is
not one of these.  If the \fBdisplay\fR submodifier is given, this only
examines non-elided characters, otherwise all characters (elided or not)
are examined.
.VE 8.5
.TP
?\fIsubmodifier\fR? \fBwordend\fR
.VS 8.5
Adjust the index to refer to the character just after the last one of the
word containing the current index.  If the current index refers to the
last character of the text then it is not modified.  If the \fBdisplay\fR
submodifier is given, this only examines non-elided characters, otherwise
all characters (elided or not) are examined.
.PP
If more than one modifier is present then they are applied in
left-to-right order.  For example, the index
.QW "\fBend \- 1 chars\fR"
refers to the next-to-last character in the text and
.QW "\fBinsert wordstart \- 1 c\fR"
refers to the character just before
the first one in the word containing the insertion cursor.  Modifiers
are applied one by one in this left to right order, and after each step
the resulting index is constrained to be a valid index in the text
widget.  So, for example, the index
.QW "\fB1.0 \-1c +1c\fR"
refers to the index
.QW \fB2.0\fR .
.PP
Where modifiers result in index changes by display lines, display chars
or display indices, and the \fIbase\fR refers to an index inside an
elided tag,
that base index is considered to be equivalent to the first following
non-elided index.
.VE 8.5
.SH TAGS
.PP
The first form of annotation in text widgets is a tag.
A tag is a textual string that is associated with some of the characters
in a text.
Tags may contain arbitrary characters, but it is probably best to
avoid using the characters
.QW " "
(space), \fB+\fR, or \fB\-\fR:
these characters have special meaning in indices, so tags containing
them cannot be used as indices.
There may be any number of tags associated with characters in a
text.
Each tag may refer to a single character, a range of characters, or
several ranges of characters.
An individual character may have any number of tags associated with it.
.PP
A priority order is defined among tags, and this order is used in
implementing some of the tag-related functions described below.
When a tag is defined (by associating it with characters or setting
its display options or binding commands to it), it is given
a priority higher than any existing tag.
The priority order of tags may be redefined using the
.QW "\fIpathName \fBtag raise\fR"
and
.QW "\fIpathName \fBtag lower\fR"
widget commands.
.PP
Tags serve three purposes in text widgets.
First, they control the way information is displayed on the screen.
By default, characters are displayed as determined by the
\fB\-background\fR, \fB\-font\fR, and \fB\-foreground\fR options for the
text widget.
However, display options may be associated with individual tags
using the
.QW "\fIpathName \fBtag configure\fR"
widget command.
If a character has been tagged, then the display options associated
with the tag override the default display style.
The following options are currently supported for tags:
.TP
\fB\-background \fIcolor\fR
\fIColor\fR specifies the background color to use for characters
associated with the tag.
It may have any of the forms accepted by \fBTk_GetColor\fR.
.TP
\fB\-bgstipple \fIbitmap\fR
\fIBitmap\fR specifies a bitmap that is used as a stipple pattern
for the background.
It may have any of the forms accepted by \fBTk_GetBitmap\fR.
If \fIbitmap\fR has not been specified, or if it is specified
as an empty string, then a solid fill will be used for the
background.
.TP
\fB\-borderwidth \fIpixels\fR
\fIPixels\fR specifies the width of a 3-D border to draw around
the background.
It may have any of the forms accepted by \fBTk_GetPixels\fR.
This option is used in conjunction with the \fB\-relief\fR
option to give a 3-D appearance to the background for characters;
it is ignored unless the \fB\-background\fR option
has been set for the tag.
.TP
\fB\-elide \fIboolean\fR
\fIElide\fR specifies whether the data should
be elided.  Elided data (characters, images, embedded windows, etc) is
not displayed and takes no space on screen, but further on behaves just
as normal data.
.TP
\fB\-fgstipple \fIbitmap\fR
\fIBitmap\fR specifies a bitmap that is used as a stipple pattern
when drawing text and other foreground information such as
underlines.
It may have any of the forms accepted by \fBTk_GetBitmap\fR.
If \fIbitmap\fR has not been specified, or if it is specified
as an empty string, then a solid fill will be used.
.TP
\fB\-font \fIfontName\fR
\fIFontName\fR is the name of a font to use for drawing characters.
It may have any of the forms accepted by \fBTk_GetFont\fR.
.TP
\fB\-foreground \fIcolor\fR
\fIColor\fR specifies the color to use when drawing text and other
foreground information such as underlines.
It may have any of the forms accepted by \fBTk_GetColor\fR.
.TP
\fB\-justify \fIjustify\fR
If the first non-elided character of a display line has a tag for which this
option has been specified, then \fIjustify\fR determines how to
justify the line.
It must be one of \fBleft\fR, \fBright\fR, or \fBcenter\fR.
If a line wraps, then the justification for each line on the
display is determined by the first non-elided character of that display line.
.TP
\fB\-lmargin1 \fIpixels\fR
If the first non-elided character of a text line has a tag for which this
option has been specified, then \fIpixels\fR specifies how
much the line should be indented from the left edge of the
window.
\fIPixels\fR may have any of the standard forms for screen
distances.
If a line of text wraps, this option only applies to the
first line on the display;  the \fB\-lmargin2\fR option controls
the indentation for subsequent lines.
.TP
\fB\-lmargin2 \fIpixels\fR
If the first non-elided character of a display line has a tag for which this
option has been specified, and if the display line is not the
first for its text line (i.e., the text line has wrapped), then
\fIpixels\fR specifies how much the line should be indented from
the left edge of the window.
\fIPixels\fR may have any of the standard forms for screen
distances.
This option is only used when wrapping is enabled, and it only
applies to the second and later display lines for a text line.
.TP
\fB\-offset \fIpixels\fR
\fIPixels\fR specifies an amount by which the text's baseline
should be offset vertically from the baseline of the overall
line, in pixels.
For example, a positive offset can be used for superscripts
and a negative offset can be used for subscripts.
\fIPixels\fR may have any of the standard forms for screen
distances.
.TP
\fB\-overstrike \fIboolean\fR
Specifies whether or not to draw a horizontal rule through
the middle of characters.
\fIBoolean\fR may have any of the forms accepted by \fBTcl_GetBoolean\fR.
.TP
\fB\-relief \fIrelief\fR
\fIRelief\fR specifies the 3-D relief to use for drawing backgrounds,
in any of the forms accepted by \fBTk_GetRelief\fR.
This option is used in conjunction with the \fB\-borderwidth\fR
option to give a 3-D appearance to the background for characters;
it is ignored unless the \fB\-background\fR option
has been set for the tag.
.TP
\fB\-rmargin \fIpixels\fR
If the first non-elided character of a display line has a tag for which this
option has been specified, then \fIpixels\fR specifies how wide
a margin to leave between the end of the line and the right
edge of the window.
\fIPixels\fR may have any of the standard forms for screen
distances.
This option is only used when wrapping is enabled.
If a text line wraps, the right margin for each line on the
display is determined by the first non-elided character of that display
line.
.TP
\fB\-spacing1 \fIpixels\fR
\fIPixels\fR specifies how much additional space should be
left above each text line, using any of the standard forms for
screen distances.
If a line wraps, this option only applies to the first
line on the display.
.TP
\fB\-spacing2 \fIpixels\fR
For lines that wrap, this option specifies how much additional
space to leave between the display lines for a single text line.
\fIPixels\fR may have any of the standard forms for screen
distances.
.TP
\fB\-spacing3 \fIpixels\fR
\fIPixels\fR specifies how much additional space should be
left below each text line, using any of the standard forms for
screen distances.
If a line wraps, this option only applies to the last
line on the display.
.TP
\fB\-tabs \fItabList\fR
\fITabList\fR specifies a set of tab stops in the same form
as for the \fB\-tabs\fR option for the text widget.  This
option only applies to a display line if it applies to the
first non-elided character on that display line.
If this option is specified as an empty string, it cancels
the option, leaving it unspecified for the tag (the default).
If the option is specified as a non-empty string that is
an empty list, such as \fB\-tags\0{\0}\fR, then it requests
default 8-character tabs as described for the \fB\-tags\fR
widget option.
.TP
\fB\-tabstyle \fIstyle\fR
\fIStyle\fR specifies either the \fItabular\fR or
\fIwordprocessor\fR style of tabbing to use for the text widget.
This option only applies to a display line if it applies to the
first non-elided character on that display line.
If this option is specified as an empty string, it cancels
the option, leaving it unspecified for the tag (the default).
.TP
\fB\-underline \fIboolean\fR
\fIBoolean\fR specifies whether or not to draw an underline underneath
characters.
It may have any of the forms accepted by \fBTcl_GetBoolean\fR.
.TP
\fB\-wrap \fImode\fR
\fIMode\fR specifies how to handle lines that are wider than the
text's window.
It has the same legal values as the \fB\-wrap\fR option
for the text widget:  \fBnone\fR, \fBchar\fR, or \fBword\fR.
If this tag option is specified, it overrides the \fB\-wrap\fR option
for the text widget.
.PP
If a character has several tags associated with it, and if their
display options conflict, then the options of the highest priority
tag are used.
If a particular display option has not been specified for a
particular tag, or if it is specified as an empty string, then
that option will never be used;  the next-highest-priority
tag's option will used instead.
If no tag specifies a particular display option, then the default
style for the widget will be used.
.PP
The second purpose for tags is event bindings.
You can associate bindings with a tag in much the same way you can
associate bindings with a widget class:  whenever particular X
events occur on characters with the given tag, a given
Tcl command will be executed.
Tag bindings can be used to give behaviors to ranges of characters;
among other things, this allows hypertext-like
features to be implemented.
For details, see the description of the
.QW "\fIpathName \fBtag bind\fR"
widget command below.
.VS 8.5
Tag bindings are shared between all peer widgets
(including any bindings for the special \fBsel\fR tag).
.VE 8.5
.PP
The third use for tags is in managing the selection.
See \fBTHE SELECTION\fR below.
.VS 8.5
With the exception of the special \fBsel\fR
tag, all tags are shared between peer text widgets, and may be
manipulated on an equal basis from any such widget.  The \fBsel\fR
tag exists separately and independently in each peer text widget (but
any tag bindings to \fBsel\fR are shared).
.VE 8.5
.SH MARKS
.PP
The second form of annotation in text widgets is a mark.
Marks are used for remembering particular places in a text.
They are something like tags, in that they have names and
they refer to places in the file, but a mark is not associated
with particular characters.
Instead, a mark is associated with the gap between two characters.
Only a single position may be associated with a mark at any given
time.
If the characters around a mark are deleted the mark will still
remain;  it will just have new neighbor characters.
In contrast, if the characters containing a tag are deleted then
the tag will no longer have an association with characters in
the file.
Marks may be manipulated with the
.QW "\fIpathName \fBmark\fR"
widget
command, and their current locations may be determined by using the
mark name as an index in widget commands.
.PP
Each mark also has a
.QW gravity ,
which is either \fBleft\fR or \fBright\fR.
The gravity for a mark specifies what happens to the mark when
text is inserted at the point of the mark.
If a mark has left gravity, then the mark is treated as if it
were attached to the character on its left, so the mark will
remain to the left of any text inserted at the mark position.
If the mark has right gravity, new text inserted at the mark
position will appear to the left of the mark (so that the mark
remains rightmost).  The gravity for a mark defaults to \fBright\fR.
.PP
The name space for marks is different from that for tags:  the
same name may be used for both a mark and a tag, but they will refer
to different things.
.PP
Two marks have special significance.
First, the mark \fBinsert\fR is associated with the insertion cursor,
as described under \fBTHE INSERTION CURSOR\fR below.
Second, the mark \fBcurrent\fR is associated with the character
closest to the mouse and is adjusted automatically to track the
mouse position and any changes to the text in the widget (one
exception:  \fBcurrent\fR is not updated in response to mouse
motions if a mouse button is down;  the update will be deferred
until all mouse buttons have been released).
Neither of these special marks may be deleted.
.VS 8.5
With the exception of
these two special marks, all marks are shared between peer text
widgets, and may be manipulated on an equal basis from any peer.
.VE 8.5
.SH "EMBEDDED WINDOWS"
.PP
The third form of annotation in text widgets is an embedded window.
Each embedded window annotation causes a window to be displayed
at a particular point in  the text.
There may be any number of embedded windows in a text widget,
and any widget may be used as an embedded window (subject to the
usual rules for geometry management, which require the text window
to be the parent of the embedded window or a descendant of its
parent).
.PP
The embedded window's position on the screen will be updated as the
text is modified or scrolled, and it will be mapped and unmapped as
it moves into and out of the visible area of the text widget.
Each embedded window occupies one
.VS 8.5
unit's
.VE 8.5
worth of index space
in the text widget, and it may be referred to either by the name
of its embedded window or by its position in the widget's
index space.
If the range of text containing the embedded window is deleted then
the window is destroyed.
.VS 8.5
Similarly if the text widget as a whole is deleted, then the window is
destroyed.
.VE 8.5
.PP
.VS 8.5
Eliding an embedded window immediately after scheduling it for creation
via \fIpathName \fBwindow create \fIindex \fB-create\fR will prevent it
from being effectively created.
Uneliding an elided embedded window scheduled for creation via
\fIpathName \fBwindow create \fIindex \fB-create\fR will automatically
trigger the associated creation script.
After destroying an elided embedded window, the latter won't get
automatically recreated.
.VE 8.5
.PP
When an embedded window is added to a text widget with the
\fIpathName \fBwindow create\fR widget command, several configuration
options may be associated with it.
These options may be  modified later with the \fIpathName \fBwindow configure\fR
widget command.
The following options are currently supported:
.TP