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'\"
'\" 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.
'\"
'\" SCCS: @(#) text.n 1.68 97/10/31 12:58:41
'\"
.so man.macros
.TH text n 4.0 Tk "Tk Built-In Commands"
.BS
'\" Note: do not modify the .SH NAME line immediately below!
.SH NAME
text \- Create and manipulate text widgets
.SH SYNOPSIS
\fBtext\fR \fIpathName \fR?\fIoptions\fR?
.SO
\-background \-highlightbackground \-insertontime \-selectborderwidth
\-borderwidth \-highlightcolor \-insertwidth \-selectforeground
\-cursor \-highlightthickness \-padx \-setgrid
\-exportselection \-insertbackground \-pady \-takefocus
\-font \-insertborderwidth \-relief \-xscrollcommand
\-foreground \-insertofftime \-selectbackground \-yscrollcommand
.SE
.SH "WIDGET-SPECIFIC OPTIONS"
.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 \-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 overriden 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 overriden 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 overriden with \fB\-spacing3\fR options in
tags.
.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
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, \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.
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.
The value of the \fBtabs\fR option may be overridden by \fB\-tabs\fR
options in tags.
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.
.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 doesn't have a uniform width then the width of the
character ``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 don't 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.
.VS
Text widgets support four different kinds of annotations on the
text, called tags, marks, embedded windows or embedded images.
.VE
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 TAGS below for more details.
.PP
The second form of annotation consists of marks, which are floating
markers in the text.
Marks are used to keep track of various interesting positions in the
text as it is edited.
See MARKS below for more details.
.PP
The third form of annotation allows arbitrary windows to be
embedded in a text widget.
See EMBEDDED WINDOWS below for more details.
.PP
.VS
The fourth form of annotation allows Tk images to be embedded in a text
widget.
See EMBEDDED IMAGES below for more details.
.VE
.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.
.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
.VS
\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.
.VE
.PP
If the \fIbase\fP could match more than one of the above forms, such
as a \fImark\fP and \fIimageName\fP 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\fB chars\fR
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 character in the text.
Spaces on either side of \fIcount\fR are optional.
.TP
\fB\- \fIcount\fB chars\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 the first character in the text.
Spaces on either side of \fIcount\fR are optional.
.TP
\fB+ \fIcount\fB lines\fR
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.
.TP
\fB\- \fIcount\fB lines\fR
Adjust the index backward by \fIcount\fR 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.
.TP
\fBlinestart\fR
Adjust the index to refer to the first character on the line.
.TP
\fBlineend\fR
Adjust the index to refer to the last character on the line (the newline).
.TP
\fBwordstart\fR
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.
.TP
\fBwordend\fR
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.
.PP
If more than one modifier is present then they are applied in
left-to-right order. For example, the index ``\fBend \- 1 chars\fR''
refers to the next-to-last character in the text and
``\fBinsert wordstart \- 1 c\fR'' refers to the character just before
the first one in the word containing the insertion cursor.
.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 the characters `` '' (space), \fB+\fR, or \fB\-\fR:
these characters have special meaning in indices, so tags containing
them can't 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
``\fIpathName \fBtag raise\fR'' and ``\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
\fBbackground\fR, \fBfont\fR, and \fBforeground\fR options for the
text widget.
However, display options may be associated with individual tags
using the ``\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 hasn't 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\-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 hasn't 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_GetFontStruct\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 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 character of that display line.
.TP
\fB\-lmargin1 \fIpixels\fR
If the first 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 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 \fBTk_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 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 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 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 \fBtags\fR
widget option.
.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 \fBTk_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 hasn't 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 \fBtag bind\fR widget
command below.
.PP
The third use for tags is in managing the selection.
See THE SELECTION below.
.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 isn't 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 ``\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 \fIgravity\fR, 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 right of the mark. 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 THE INSERTION CURSOR 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.
.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).
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 character's 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.
.PP
When an embedded window is added to a text widget with the
\fBwindow create\fR widget command, several configuration
options may be associated with it.
These options may be modified later with the \fBwindow configure\fR
widget command.
The following options are currently supported:
.TP
\fB\-align \fIwhere\fR
If the window is not as tall as the line in which it is displayed,
this option determines where the window is displayed in the line.
\fIWhere\fR must have one of the values \fBtop\fR (align the top of the window
with the top of the line), \fBcenter\fR (center the window
within the range of the line), \fBbottom\fR (align the bottom of the
window with the bottom of the line's area),
or \fBbaseline\fR (align the bottom of the window with the baseline
of the line).
.TP
\fB\-create \fIscript\fR
Specifies a Tcl script that may be evaluated to create the window
for the annotation.
If no \fB\-window\fR option has been specified for the annotation
this script will be evaluated when the annotation is about to
be displayed on the screen.
\fIScript\fR must create a window for the annotation and return
the name of that window as its result.
If the annotation's window should ever be deleted, \fIscript\fR
will be evaluated again the next time the annotation is displayed.
.TP
\fB\-padx \fIpixels\fR
\fIPixels\fR specifies the amount of extra space to leave on
each side of the embedded window.
It may have any of the usual forms defined for a screen distance.
.TP
\fB\-pady \fIpixels\fR
\fIPixels\fR specifies the amount of extra space to leave on
the top and on the bottom of the embedded window.
It may have any of the usual forms defined for a screen distance.
.TP
\fB\-stretch \fIboolean\fR
If the requested height of the embedded window is less than the
height of the line in which it is displayed, this option can be
used to specify whether the window should be stretched vertically
to fill its line.
If the \fB\-pady\fR option has been specified as well, then the
requested padding will be retained even if the window is
stretched.
.TP
\fB\-window \fIpathName\fR
Specifies the name of a window to display in the annotation.
.VS
.SH EMBEDDED IMAGES
.PP
The final form of annotation in text widgets is an embedded image.
Each embedded image annotation causes an image to be displayed
at a particular point in the text.
There may be any number of embedded images in a text widget,
and a particular image may be embedded in multiple places in the same
text widget.
The embedded image's position on the screen will be updated as the
text is modified or scrolled.
Each embedded image occupies one character's worth of index space
in the text widget, and it may be referred to either by
its position in the widget's index space, or the name it is assigned
when the image is inserted into the text widget widh \fBimage create\fP.
If the range of text containing the embedded image is deleted then
that copy of the image is removed from the screen.
.PP
When an embedded image is added to a text widget with the \fBimage
create\fR widget command, a name unique to this instance of the image
is returned. This name may then be used to refer to this image
instance. The name is taken to be the value of the \fB-name\fP option
(described below). If the \fB-name\fP option is not provided, the
\fB-image\fP name is used instead. If the \fIimageName\fP is already
in use in the text widget, then \fB#\fInn\fR is added to the end of the
\fIimageName\fP, where \fInn\fP is an arbitrary integer. This insures
the \fIimageName\fP is unique.
Once this name is assigned to this instance of the image, it does not
change, even though the \fB-image\fP or \fB-name\fP values can be changed
with \fBimage configure\fP.
.PP
When an embedded image is added to a text widget with the
\fBimage create\fR widget command, several configuration
options may be associated with it.
These options may be modified later with the \fBimage configure\fR
widget command.
The following options are currently supported:
.TP
\fB\-align \fIwhere\fR
If the image is not as tall as the line in which it is displayed,
this option determines where the image is displayed in the line.
\fIWhere\fR must have one of the values \fBtop\fR (align the top of the image
with the top of the line), \fBcenter\fR (center the image
within the range of the line), \fBbottom\fR (align the bottom of the
image with the bottom of the line's area),
or \fBbaseline\fR (align the bottom of the image with the baseline
of the line).
.TP
\fB\-image \fIimage\fR
Specifies the name of the Tk image to display in the annotation.
If \fIimage\fP is not a valid Tk image, then an error is returned.
.TP
\fB\-name \fIImageName\fR
Specifies the name by which this image instance may be referenced in
the text widget. If \fIImageName\fP is not supplied, then the
name of the Tk image is used instead.
If the \fIimageName\fP is already in use, \fI#nn\fP is appended to
the end of the name as described above.
.TP
\fB\-padx \fIpixels\fR
\fIPixels\fR specifies the amount of extra space to leave on
each side of the embedded image.
It may have any of the usual forms defined for a screen distance.
.TP
\fB\-pady \fIpixels\fR
\fIPixels\fR specifies the amount of extra space to leave on
the top and on the bottom of the embedded image.
It may have any of the usual forms defined for a screen distance.
.VE
.SH THE SELECTION
.PP
Selection support is implemented via tags.
If the \fBexportSelection\fR option for the text widget is true
then the \fBsel\fR tag will be associated with the selection:
.IP [1]
Whenever characters are tagged with \fBsel\fR the text widget
will claim ownership of the selection.
.IP [2]
Attempts to retrieve the
selection will be serviced by the text widget, returning all the
characters with the \fBsel\fR tag.
.IP [3]
If the selection is claimed away by another application or by another
window within this application, then the \fBsel\fR tag will be removed
from all characters in the text.
.PP
The \fBsel\fR tag is automatically defined when a text widget is
created, and it may not be deleted with the ``\fIpathName \fBtag delete\fR''
widget command. Furthermore, the \fBselectBackground\fR,
\fBselectBorderWidth\fR, and \fBselectForeground\fR options for
the text widget are tied to the \fB\-background\fR,
\fB\-borderwidth\fR, and \fB\-foreground\fR options for the \fBsel\fR
tag: changes in either will automatically be reflected in the
other.
.SH THE INSERTION CURSOR
.PP
The mark named \fBinsert\fR has special significance in text widgets.
It is defined automatically when a text widget is created and it
may not be unset with the ``\fIpathName \fBmark unset\fR'' widget
command.
The \fBinsert\fR mark represents the position of the insertion
cursor, and the insertion cursor will automatically be drawn at
this point whenever the text widget has the input focus.
.SH "WIDGET COMMAND"
.PP
The \fBtext\fR command creates a new Tcl command whose
name is the same as the path name of the text's window. This
command may be used to invoke various
operations on the widget. It has the following general form:
.CS
\fIpathName option \fR?\fIarg arg ...\fR?
.CE
\fIPathName\fR is the name of the command, which is the same as
the text widget's path name. \fIOption\fR and the \fIarg\fRs
determine the exact behavior of the command. The following
commands are possible for text widgets:
.TP
\fIpathName \fBbbox \fIindex\fR
Returns a list of four elements describing the screen area
of the character given by \fIindex\fR.
The first two elements of the list give the x and y coordinates
of the upper-left corner of the area occupied by the
character, and the last two elements give the width and height
of the area.
If the character is only partially visible on the screen, then
the return value reflects just the visible part.
If the character is not visible on the screen then the return
value is an empty list.
.TP
\fIpathName \fBcget\fR \fIoption\fR
Returns the current value of the configuration option given
by \fIoption\fR.
\fIOption\fR may have any of the values accepted by the \fBtext\fR
command.
.TP
\fIpathName \fBcompare\fR \fIindex1 op index2\fR
Compares the indices given by \fIindex1\fR and \fIindex2\fR according
to the relational operator given by \fIop\fR, and returns 1 if
the relationship is satisfied and 0 if it isn't.
\fIOp\fR must be one of the operators <, <=, ==, >=, >, or !=.
If \fIop\fR is == then 1 is returned if the two indices refer to
the same character, if \fIop\fR is < then 1 is returned if \fIindex1\fR
refers to an earlier character in the text than \fIindex2\fR, and
so on.
.TP
\fIpathName \fBconfigure\fR ?\fIoption\fR? \fI?value option value ...\fR?
Query or modify the configuration options of the widget.
If no \fIoption\fR is specified, returns a list describing all of
the available options for \fIpathName\fR (see \fBTk_ConfigureInfo\fR for
information on the format of this list). If \fIoption\fR is specified
with no \fIvalue\fR, then the command returns a list describing the
one named option (this list will be identical to the corresponding
sublist of the value returned if no \fIoption\fR is specified). If
one or more \fIoption\-value\fR pairs are specified, then the command
modifies the given widget option(s) to have the given value(s); in
this case the command returns an empty string.
\fIOption\fR may have any of the values accepted by the \fBtext\fR
command.
.TP
\fIpathName \fBdebug \fR?\fIboolean\fR?
If \fIboolean\fR is specified, then it must have one of the true or
false values accepted by Tcl_GetBoolean.
If the value is a true one then internal consistency checks will be
turned on in the B-tree code associated with text widgets.
If \fIboolean\fR has a false value then the debugging checks will
be turned off.
In either case the command returns an empty string.
If \fIboolean\fR is not specified then the command returns \fBon\fR
or \fBoff\fR to indicate whether or not debugging is turned on.
There is a single debugging switch shared by all text widgets: turning
debugging on or off in any widget turns it on or off for all widgets.
For widgets with large amounts of text, the consistency checks may
cause a noticeable slow-down.
.TP
\fIpathName \fBdelete \fIindex1 \fR?\fIindex2\fR?
Delete a range of characters from the text.
If both \fIindex1\fR and \fIindex2\fR are specified, then delete
all the characters starting with the one given by \fIindex1\fR
and stopping just before \fIindex2\fR (i.e. the character at
\fIindex2\fR is not deleted).
If \fIindex2\fR doesn't specify a position later in the text
than \fIindex1\fR then no characters are deleted.
If \fIindex2\fR isn't specified then the single character at
\fIindex1\fR is deleted.
It is not allowable to delete characters in a way that would leave
the text without a newline as the last character.
The command returns an empty string.
.TP
\fIpathName \fBdlineinfo \fIindex\fR
Returns a list with five elements describing the area occupied
by the display line containing \fIindex\fR.
The first two elements of the list give the x and y coordinates
of the upper-left corner of the area occupied by the
line, the third and fourth elements give the width and height
of the area, and the fifth element gives the position of the baseline
for the line, measured down from the top of the area.
All of this information is measured in pixels.
If the current wrap mode is \fBnone\fR and the line extends beyond
the boundaries of the window,
the area returned reflects the entire area of the line, including the
portions that are out of the window.
If the line is shorter than the full width of the window then the
area returned reflects just the portion of the line that is occupied
by characters and embedded windows.
If the display line containing \fIindex\fR is not visible on
the screen then the return value is an empty list.
.TP
\fIpathName \fBdump \fR?\fIswitches\fR? \fIindex1 \fR?\fIindex2\fR?
Return the contents of the text widget from \fIindex1\fR up to,
but not including \fIindex2\fR,
including the text and
information about marks, tags, and embedded windows.
If \fIindex2\fR is not specified, then it defaults to
one character past \fIindex1\fR. The information is returned
in the following format:
.LP
.RS
\fIkey1 value1 index1 key2 value2 index2\fR ...
.LP
The possible \fIkey\fP values are \fBtext\fP, \fBmark\fP,
\fBtagon\fP, \fBtagoff\fP, and \fBwindow\fP. The corresponding
\fIvalue\fP is the text, mark name, tag name, or window name.
The \fIindex\fP information is the index of the
start of the text, the mark, the tag transition, or the window.
One or more of the following switches (or abbreviations thereof)
may be specified to control the dump:
.TP
\fB\-all\fR
Return information about all elements: text, marks, tags, and windows.
This is the default.
.TP
\fB\-command \fIcommand\fR
Instead of returning the information as the result of the dump operation,
invoke the \fIcommand\fR on each element of the text widget within the range.
The command has three arguments appended to it before it is evaluated:
the \fIkey\fP, \fIvalue\fP, and \fIindex\fP.
.TP
\fB\-mark\fR
Include information about marks in the dump results.
.TP
\fB\-tag\fR
Include information about tag transitions in the dump results. Tag information is
returned as \fBtagon\fP and \fBtagoff\fP elements that indicate the
begin and end of each range of each tag, respectively.
.TP
\fB\-text\fR
Include information about text in the dump results. The value is the
text up to the next element or the end of range indicated by \fIindex2\fR.
A text element does not span newlines. A multi-line block of text that
contains no marks or tag transitions will still be dumped as a set
of text seqments that each end with a newline. The newline is part
of the value.
.TP
\fB\-window\fR
Include information about embedded windows in the dump results.
The value of a window is its Tk pathname, unless the window
has not been created yet. (It must have a create script.)
In this case an empty string is returned, and you must query the
window by its index position to get more information.
.RE
.TP
\fIpathName \fBget \fIindex1 \fR?\fIindex2\fR?
Return a range of characters from the text.
The return value will be all the characters in the text starting
with the one whose index is \fIindex1\fR and ending just before
the one whose index is \fIindex2\fR (the character at \fIindex2\fR
will not be returned).
If \fIindex2\fR is omitted then the single character at \fIindex1\fR
is returned.
If there are no characters in the specified range (e.g. \fIindex1\fR
is past the end of the file or \fIindex2\fR is less than or equal
to \fIindex1\fR) then an empty string is returned.
If the specified range contains embedded windows, no information
about them is included in the returned string.
.TP
\fIpathName \fBimage \fIoption \fR?\fIarg arg ...\fR?
This command is used to manipulate embedded images.
The behavior of the command depends on the \fIoption\fR argument
that follows the \fBtag\fR argument.
The following forms of the command are currently supported:
.RS
.TP
\fIpathName \fBimage cget\fR \fIindex option\fR
Returns the value of a configuration option for an embedded image.
\fIIndex\fR identifies the embedded image, and \fIoption\fR
specifies a particular configuration option, which must be one of
the ones listed in the section EMBEDDED IMAGES.
.TP
\fIpathName \fBimage configure \fIindex\fR ?\fIoption value ...\fR?
Query or modify the configuration options for an embedded image.
If no \fIoption\fR is specified, returns a list describing all of
the available options for the embedded image at \fIindex\fR
(see \fBTk_ConfigureInfo\fR for information on the format of this list).
If \fIoption\fR is specified with no \fIvalue\fR, then the command
returns a list describing the one named option (this list will be
identical to the corresponding sublist of the value returned if no
\fIoption\fR is specified).
If one or more \fIoption\-value\fR pairs are specified, then the command
modifies the given option(s) to have the given value(s); in
this case the command returns an empty string.
See EMBEDDED IMAGES for information on the options that
are supported.
.TP
\fIpathName \fBimage create \fIindex\fR ?\fIoption value ...\fR?
This command creates a new image annotation, which will appear
in the text at the position given by \fIindex\fR.
Any number of \fIoption\-value\fR pairs may be specified to
configure the annotation.
Returns a unique identifier that may be used as an index to refer to
this image.
See EMBEDDED IMAGES for information on the options that
are supported, and a description of the identifier returned.
.TP
\fIpathName \fBimage names\fR
Returns a list whose elements are the names of all image instances currently
embedded in \fIwindow\fR.
.RE
.TP
\fIpathName \fBindex \fIindex\fR
Returns the position corresponding to \fIindex\fR in the form
\fIline.char\fR where \fIline\fR is the line number and \fIchar\fR
is the character number.
\fIIndex\fR may have any of the forms described under INDICES above.
.TP
\fIpathName \fBinsert \fIindex chars \fR?\fItagList chars tagList ...\fR?
Inserts all of the \fIchars\fR arguments just before the character at
\fIindex\fR.
If \fIindex\fR refers to the end of the text (the character after
the last newline) then the new text is inserted just before the
last newline instead.
If there is a single \fIchars\fR argument and no \fItagList\fR, then
the new text will receive any tags that are present on both the
character before and the character after the insertion point; if a tag
is present on only one of these characters then it will not be
applied to the new text.
If \fItagList\fR is specified then it consists of a list of
tag names; the new characters will receive all of the tags in
this list and no others, regardless of the tags present around
the insertion point.
If multiple \fIchars\fR\-\fItagList\fR argument pairs are present,
they produce the same effect as if a separate \fBinsert\fR widget
command had been issued for each pair, in order.
The last \fItagList\fR argument may be omitted.
.TP
\fIpathName \fBmark \fIoption \fR?\fIarg arg ...\fR?
This command is used to manipulate marks. The exact behavior of
the command depends on the \fIoption\fR argument that follows
the \fBmark\fR argument. The following forms of the command
are currently supported:
.RS
.TP
\fIpathName \fBmark gravity \fImarkName\fR ?\fIdirection\fR?
If \fIdirection\fR is not specified, returns \fBleft\fR or \fBright\fR
to indicate which of its adjacent characters \fImarkName\fR is attached
to.
If \fIdirection\fR is specified, it must be \fBleft\fR or \fBright\fR;
the gravity of \fImarkName\fR is set to the given value.
.TP
\fIpathName \fBmark names\fR
Returns a list whose elements are the names of all the marks that
are currently set.
.TP
\fIpathName \fBmark next \fIindex\fR
Returns the name of the next mark at or after \fIindex\fR.
If \fIindex\fR is specified in numerical form, then the search for
the next mark begins at that index.
If \fIindex\fR is the name of a mark, then the search for
the next mark begins immediately after that mark.
This can still return a mark at the same position if
there are multiple marks at the same index.
These semantics mean that the \fBmark next\fP operation can be used to
step through all the marks in a text widget in the same order
as the mark information returned by the \fBdump\fP operation.
If a mark has been set to the special \fBend\fP index,
then it appears to be \fIafter\fP \fBend\fP with respect to the \fBmark next\fP operation.
An empty string is returned if there are no marks after \fIindex\fR.
.TP
\fIpathName \fBmark previous \fIindex\fR
Returns the name of the mark at or before \fIindex\fR.
If \fIindex\fR is specified in numerical form, then the search for
the previous mark begins with the character just before that index.
If \fIindex\fR is the name of a mark, then the search for
the next mark begins immediately before that mark.
This can still return a mark at the same position if
there are multiple marks at the same index.
These semantics mean that the \fBmark previous\fP operation can be used to
step through all the marks in a text widget in the reverse order
as the mark information returned by the \fBdump\fP operation.
An empty string is returned if there are no marks before \fIindex\fR.
.TP
\fIpathName \fBmark set \fImarkName index\fR
Sets the mark named \fImarkName\fR to a position just before the
character at \fIindex\fR.
If \fImarkName\fR already exists, it is moved from its old position;
if it doesn't exist, a new mark is created.
This command returns an empty string.
.TP
\fIpathName \fBmark unset \fImarkName \fR?\fImarkName markName ...\fR?
Remove the mark corresponding to each of the \fImarkName\fR arguments.
The removed marks will not be usable in indices and will not be
returned by future calls to ``\fIpathName \fBmark names\fR''.
This command returns an empty string.
.RE
.TP
\fIpathName \fBscan\fR \fIoption args\fR
This command is used to implement scanning on texts. It has