<?xml version="1.0" encoding="UTF-8"?>
<chapter id="dialog-macro">
    <title>A Dialog-Based Macro</title>

    <!-- jEdit 4.0 Macro Guide, (C) 2001, 2002 John Gellene                 -->

    <!-- jEdit buffer-local properties:                                     -->

    <!-- :indentSize=1:noTabs=yes:maxLineLen=72:tabSize=2:                  -->

    <!-- :xml.root=users-guide.xml:                                         -->

    <!-- This file contains an extended discussion of a                     -->

    <!-- dialog-based macro example "Add_Prefix_and_Suffix.bsh"             -->

    <!-- $Id: dialog-macro.xml 9995 2007-07-10 23:22:40Z Vampire0 $      -->

    <para>Now we will look at a more complicated macro which will demonstrate
    some useful techniques and BeanShell features.</para>

    <sect1 id="dialog-macro-intro">
        <title>Use of the Macro</title>

        <para>Our new example adds prefix and suffix text to a series of
        selected lines. This macro can be used to reduce typing for a series of
        text items that must be preceded and following by identical text. In
        Java, for example, if we are interested in making a series of calls to
        <function>StringBuffer.append()</function> to construct a lengthy,
        formatted string, we could type the parameter for each call on
        successive lines as follows:</para>

        <screen>profileString_1
secretThing.toString()
name
address
addressSupp
city
<quote>state/province</quote>
country</screen>

        <para>Our macro would ask for input for the common <quote>prefix</quote>
        and <quote>suffix</quote> to be applied to each line; in this case, the
        prefix is <userinput>ourStringBuffer.append(</userinput> and the suffix
        is <userinput>);</userinput>. After selecting these lines and running
        the macro, the resulting text would look like this:</para>

        <screen>ourStringBuffer.append(profileString_1);
ourStringBuffer.append(secretThing.toString());
ourStringBuffer.append(name);
ourStringBuffer.append(address);
ourStringBuffer.append(addressSupp);
ourStringBuffer.append(city);
ourStringBuffer.append(<quote>state/province</quote>);
ourStringBuffer.append(country);</screen>
    </sect1>

    <sect1 id="add-prefix-and-suffix">
        <title>Listing of the Macro</title>

        <para>The macro script follows. You can find it in the jEdit
        distribution in the <filename>Text</filename> subdirectory of the
        <filename>macros</filename> directory. You can also try it out by
        invoking
        <guimenu>Macros</guimenu>&gt;<guisubmenu>Text</guisubmenu>&gt;<guimenuitem>Add
        Prefix and Suffix</guimenuitem>.</para>

        <informalexample>
            <!-- <title>Add_Prefix_and_Suffix.bsh</title> -->

            <programlisting>// beginning of Add_Prefix_and_Suffix.bsh

<anchor id="imports" />// import statement (see <xref linkend="explain-imports" />)
import javax.swing.border.*;

<anchor id="main-routine" />// main routine
void prefixSuffixDialog()
{
<anchor id="create-dialog" />    // create dialog object (see <xref
                    linkend="explain-create-dialog" />)
    title = <quote>Add prefix and suffix to selected lines</quote>;
    dialog = new JDialog(view, title, false);
    content = new JPanel(new BorderLayout());
    content.setBorder(new EmptyBorder(12, 12, 12, 12));
    content.setPreferredSize(new Dimension(320, 160));
    dialog.setContentPane(content);

<anchor id="fields-panel" />    // add the text fields (see <xref
                    linkend="explain-fields-panel" />)
    fieldPanel = new JPanel(new GridLayout(4, 1, 0, 6));
    prefixField = new HistoryTextField(<quote>macro.add-prefix</quote>);
    prefixLabel = new JLabel(<quote>Prefix to add:</quote>);
    suffixField = new HistoryTextField(<quote>macro.add-suffix</quote>);
    suffixLabel = new JLabel(<quote>Suffix to add:</quote>);
    fieldPanel.add(prefixLabel);
    fieldPanel.add(prefixField);
    fieldPanel.add(suffixLabel);
    fieldPanel.add(suffixField);
    content.add(fieldPanel, <quote>Center</quote>);

<anchor id="button-panel" />    // add a panel containing the buttons (see <xref
                    linkend="explain-button-panel" />)
    buttonPanel = new JPanel();
    buttonPanel.setLayout(new BoxLayout(buttonPanel,
        BoxLayout.X_AXIS));
    buttonPanel.setBorder(new EmptyBorder(12, 50, 0, 50));
    buttonPanel.add(Box.createGlue());
    ok = new JButton(<quote>OK</quote>);
    cancel = new JButton(<quote>Cancel</quote>);
    ok.setPreferredSize(cancel.getPreferredSize());
    dialog.getRootPane().setDefaultButton(ok);
    buttonPanel.add(ok);
    buttonPanel.add(Box.createHorizontalStrut(6));
    buttonPanel.add(cancel);
    buttonPanel.add(Box.createGlue());
    content.add(buttonPanel, <quote>South</quote>);

<anchor id="add-listeners" />    // register this method as an ActionListener for
    // the buttons and text fields (see <xref linkend="explain-add-listeners" />)
    ok.addActionListener(this);
    cancel.addActionListener(this);
    prefixField.addActionListener(this);
    suffixField.addActionListener(this);

<anchor id="set-visible" />    // locate the dialog in the center of the
    // editing pane and make it visible (see <xref linkend="explain-set-visible" />)
    dialog.pack();
    dialog.setLocationRelativeTo(view);
    dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
    dialog.setVisible(true);

<anchor id="action-listener" />    // this method will be called when a button is clicked
    // or when ENTER is pressed (see <xref linkend="explain-action-listener" />)
    void actionPerformed(e)
    {
        if(e.getSource() != cancel)
        {
            processText();
        }
        dialog.dispose();
    }

<anchor id="process-text" />    // this is where the work gets done to insert
    // the prefix and suffix (see <xref linkend="explain-process-text" />)
    void processText()
    {
        prefix = prefixField.getText();
        suffix = suffixField.getText();
        if(prefix.length() == 0 &amp;&amp; suffix.length() == 0)
            return;
        prefixField.addCurrentToHistory();
        suffixField.addCurrentToHistory();

<anchor id="jEdit-calls" />        // text manipulation begins here using calls
        // to jEdit methods  (see <xref linkend="explain-jedit-calls" />)
        buffer.beginCompoundEdit();
        selectedLines = textArea.getSelectedLines();
        for(i = 0; i &lt; selectedLines.length; ++i)
        {
            offsetBOL = textArea.getLineStartOffset(
                selectedLines[i]);
            textArea.setCaretPosition(offsetBOL);
            textArea.goToStartOfWhiteSpace(false);
            textArea.goToEndOfWhiteSpace(true);
            text = textArea.getSelectedText();
            if(text == null) text = "";
            textArea.setSelectedText(prefix + text + suffix);
        }
        buffer.endCompoundEdit();
    }
}

<anchor id="main" />// this single line of code is the script's main routine
// (see <xref linkend="explain-main" />)
prefixSuffixDialog();

// end of Add_Prefix_and_Suffix.bsh</programlisting>
        </informalexample>
    </sect1>

    <sect1 id="macro-analysis">
        <title>Analysis of the Macro</title>

        <sect2 id="explain-imports">
            <title>Import Statements</title>

            <informalexample>
                <programlisting>// import statement
import javax.swing.border.*;</programlisting>
            </informalexample>

            <para>This macro makes use of classes in the
            <literal>javax.swing.border</literal> package, which is not
            automatically imported. As we mentioned previously (see <xref
            linkend="first-example" />), jEdit's implementation of BeanShell
            causes a number of classes to be automatically imported. Classes
            that are not automatically imported must be identified by a full
            qualified name or be the subject of an <function>import</function>
            statement.</para>
        </sect2>

        <sect2 id="explain-create-dialog">
            <title>Create the Dialog</title>

            <informalexample>
                <programlisting>// create dialog object
title = <quote>Add prefix and suffix to selected lines</quote>;
dialog = new JDialog(view, title, false);
content = new JPanel(new BorderLayout());
content.setBorder(new EmptyBorder(12, 12, 12, 12));
dialog.setContentPane(content);</programlisting>
            </informalexample>

            <para>To get input for the macro, we need a dialog that provides for
            input of the prefix and suffix strings, an <guibutton>OK</guibutton>
            button to perform text insertion, and a
            <guibutton>Cancel</guibutton> button in case we change our mind. We
            have decided to make the dialog window non-modal. This will allow us
            to move around in the text buffer to find things we may need
            (including text to cut and paste) while the macro is running and the
            dialog is visible.</para>

            <para>The Java object we need is a <classname>JDialog</classname>
            object from the Swing package. To construct one, we use the
            <function>new</function> keyword and call a
            <glossterm>constructor</glossterm> function. The constructor we use
            takes three parameters: the owner of the new dialog, the title to be
            displayed in the dialog frame, and a <classname>boolean</classname>
            parameter (<constant>true</constant> or <constant>false</constant>)
            that specifies whether the dialog will be modal or non-modal. We
            define the variable <varname>title</varname> using a string literal,
            then use it immediately in the <classname>JDialog</classname>
            constructor.</para>

            <para>A <classname>JDialog</classname> object is a window containing
            a single object called a <glossterm>content pane</glossterm>. The
            content pane in turn contains the various visible components of the
            dialog. A <classname>JDialog</classname> creates an empty content
            pane for itself as during its construction. However, to control the
            dialog's appearance as much as possible, we will separately create
            our own content pane and attach it to the
            <classname>JDialog</classname>. We do this by creating a
            <classname>JPanel</classname> object. A
            <classname>JPanel</classname> is a lightweight container for other
            components that can be set to a given size and color. It also
            contains a <glossterm>layout</glossterm> scheme for arranging the
            size and position of its components. Here we are constructing a
            <classname>JPanel</classname> as a content pane with a
            <classname>BorderLayout</classname>. We put a
            <classname>EmptyBorder</classname> inside it to serve as a margin
            between the edge of the window and the components inside. We then
            attach the <classname>JPanel</classname> as the dialog's content
            pane, replacing the dialog's home-grown version.</para>

            <para>A <classname>BorderLayout</classname> is one of the simpler
            layout schemes available for container objects like
            <classname>JPanel</classname>. A <classname>BorderLayout</classname>
            divides the container into five sections: <quote>North</quote>,
            <quote>South</quote>, <quote>East</quote>, <quote>West</quote> and
            <quote>Center</quote>. Components are added to the layout using the
            container's <function>add</function> method, specifying the
            component to be added and the section to which it is assigned.
            Building a component like our dialog window involves building a set
            of nested containers and specifying the location of each of their
            member components. We have taken the first step by creating a
            <classname>JPanel</classname> as the dialog's content pane.</para>
        </sect2>

        <sect2 id="explain-fields-panel">
            <title>Create the Text Fields</title>

            <informalexample>
                <programlisting>// add the text fields
fieldPanel = new JPanel(new GridLayout(4, 1, 0, 6));
prefixField = new HistoryTextField("macro.add-prefix");
prefixLabel = new JLabel(<quote>Prefix to add</quote>:);
suffixField = new HistoryTextField(<quote>macro.add-suffix</quote>);
suffixLabel = new JLabel(<quote>Suffix to add:</quote>);
fieldPanel.add(prefixLabel);
fieldPanel.add(prefixField);
fieldPanel.add(suffixLabel);
fieldPanel.add(suffixField);
content.add(fieldPanel, <quote>Center</quote>);</programlisting>
            </informalexample>

            <para>Next we shall create a smaller panel containing two fields for
            entering the prefix and suffix text and two labels identifying the
            input fields.</para>

            <para>For the text fields, we will use jEdit's <ulink
            url="../api/org/gjt/sp/jedit/gui/HistoryTextField.html">HistoryTextField</ulink>
            class. It is derived from the Java Swing class
            <classname>JTextField</classname>. This class offers the enhancement
            of a stored list of prior values used as text input. When the
            component has input focus, the up and down keys scroll through the
            prior values for the variable. <!-- The prior values are stored in a file named
    <filename>history</filename> located in the directory in which jEdit stores
    various user data. --></para>

            <para>To create the <ulink
            url="../api/org/gjt/sp/jedit/gui/HistoryTextField.html">HistoryTextField</ulink>
            objects we use a constructor method that takes a single parameter:
            the name of the tag under which history values will be stored. Here
            we choose names that are not likely to conflict with existing jEdit
            history items.</para>

            <para>The labels that accompany the text fields are
            <classname>JLabel</classname> objects from the Java Swing package.
            The constructor we use for both labels takes the label text as a
            single <classname>String</classname> parameter.</para>

            <para>We wish to arrange these four components from top to bottom,
            one after the other. To achieve that, we use a
            <classname>JPanel</classname> container object named
            <varname>fieldPanel</varname> that will be nested inside the
            dialog's content pane that we have already created. In the
            constructor for <varname>fieldPanel</varname>, we assign a new
            <classname>GridLayout</classname> with the indicated parameters:
            four rows, one column, zero spacing between columns (a meaningless
            element of a grid with only one column, but nevertheless a required
            parameter) and spacing of six pixels between rows. The spacing
            between rows spreads out the four <quote>grid</quote> elements.
            After the components, the panel and the layout are specified, the
            components are added to <varname>fieldPanel</varname> top to bottom,
            one <quote>grid cell</quote> at a time. Finally, the complete
            <varname>fieldPanel</varname> is added to the dialog's content pane
            to occupy the <quote>Center</quote> section of the content
            pane.</para>
        </sect2>

        <sect2 id="explain-button-panel">
            <title>Create the Buttons</title>

            <informalexample>
                <programlisting>// add the buttons
buttonPanel = new JPanel();
buttonPanel.setLayout(new BoxLayout(buttonPanel,
    BoxLayout.X_AXIS));
buttonPanel.setBorder(new EmptyBorder(12, 50, 0, 50));
buttonPanel.add(Box.createGlue());
ok = new JButton(<quote>OK</quote>);
cancel = new JButton(<quote>Cancel</quote>);
ok.setPreferredSize(cancel.getPreferredSize());
dialog.getRootPane().setDefaultButton(ok);
buttonPanel.add(ok);
buttonPanel.add(Box.createHorizontalStrut(6));
buttonPanel.add(cancel);
buttonPanel.add(Box.createGlue());
content.add(buttonPanel, <quote>South</quote>);</programlisting>
            </informalexample>

            <para>To create the dialog's buttons, we follow repeat the
            <quote>nested container</quote> pattern we used in creating the text
            fields. First, we create a new, nested panel. This time we use a
            <classname>BoxLayout</classname> that places components either in a
            single row or column, depending on the parameter passed to its
            constructor. This layout object is more flexible than a
            <classname>GridLayout</classname> in that variable spacing between
            elements can be specified easily. We put an
            <classname>EmptyBorder</classname> in the new panel to set margins
            for placing the buttons. Then we create the buttons, using a
            <classname>JButton</classname> constructor that specifies the button
            text. After setting the size of the <guilabel>OK</guilabel> button
            to equal the size of the <guilabel>Cancel</guilabel> button, we
            designate the <guilabel>OK</guilabel> button as the default button
            in the dialog. This causes the <guilabel>OK</guilabel> button to be
            outlined when the dialog if first displayed. Finally, we place the
            buttons side by side with a 6 pixel gap between them (for aesthetic
            reasons), and place the completed <varname>buttonPanel</varname> in
            the <quote>South</quote> section of the dialog's content
            pane.</para>
        </sect2>

        <sect2 id="explain-add-listeners">
            <title>Register the Action Listeners</title>

            <informalexample>
                <programlisting>// register this method as an ActionListener for
// the buttons and text fields
ok.addActionListener(this);
cancel.addActionListener(this);
prefixField.addActionListener(this);
suffixField.addActionListener(this);</programlisting>
            </informalexample>

            <para>In order to specify the action to be taken upon clicking a
            button or pressing the <keycap>Enter</keycap> key, we must register
            an <classname>ActionListener</classname> for each of the four active
            components of the dialog - the two <ulink
            url="../api/org/gjt/sp/jedit/HistoryTextField.html">HistoryTextField</ulink>
            components and the two buttons. In Java, an
            <classname>ActionListener</classname> is an
            <glossterm>interface</glossterm> - an abstract specification for a
            derived class to implement. The
            <classname>ActionListener</classname> interface contains a single
            method to be implemented:</para>

            <funcsynopsis>
                <funcprototype>
                    <funcdef>public void
                    <function>actionPerformed</function></funcdef>

                    <paramdef>ActionEvent <parameter>e</parameter></paramdef>
                </funcprototype>
            </funcsynopsis>

            <para>BeanShell does not permit a script to create derived classes.
            However, BeanShell offers a useful substitute: a method can be used
            as a scripted object that can include nested methods implementing a
            number of Java interfaces. The method
            <function>prefixSuffixDialog()</function> that we are writing can
            thus be treated as an <classname>ActionListener</classname> object.
            To accomplish this, we call <function>addActionListener()</function>
            on each of the four components specifying <varname>this</varname> as
            the <classname>ActionListener</classname>. We still need to
            implement the interface. We will do that shortly.</para>
        </sect2>

        <sect2 id="explain-set-visible">
            <title>Make the Dialog Visible</title>

            <informalexample>
                <programlisting>// locate the dialog in the center of the
// editing pane and make it visible
dialog.pack();
dialog.setLocationRelativeTo(view);
dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
dialog.setVisible(true);</programlisting>
            </informalexample>

            <para>Here we do three things. First, we activate all the layout
            routines we have established by calling the
            <function>pack()</function> method for the dialog as the top-level
            window. Next we center the dialog's position in the active jEdit
            <varname>view</varname> by calling
            <function>setLocationRelativeTo()</function> on the dialog. We also
            call the <function>setDefaultCloseOperation()</function> function to
            specify that the dialog box should be immediately disposed if the
            user clicks the close box. Finally, we activate the dialog by
            calling <function>setVisible()</function>with the state parameter
            set to <constant>true</constant>.</para>

            <para>At this point we have a decent looking dialog window that
            doesn't do anything. Without more code, it will not respond to user
            input and will not accomplish any text manipulation. The remainder
            of the script deals with these two requirements.</para>
        </sect2>

        <sect2 id="explain-action-listener">
            <title>The Action Listener</title>

            <informalexample>
                <programlisting>// this method will be called when a button is clicked
// or when ENTER is pressed
void actionPerformed(e)
{
    if(e.getSource() != cancel)
    {
        processText();
    }
    dialog.dispose();
}</programlisting>
            </informalexample>

            <para>The method <function>actionPerformed()</function> nested
            inside <function>prefixSuffixDialog()</function> implements the
            implicit <classname>ActionListener</classname> interface. It looks
            at the source of the <classname>ActionEvent</classname>, determined
            by a call to <function>getSource()</function>. What we do with this
            return value is straightforward: if the source is not the
            <guibutton>Cancel</guibutton> button, we call the
            <function>processText()</function> method to insert the prefix and
            suffix text. Then the dialog is closed by calling its
            <function>dispose()</function> method.</para>

            <para>The ability to implement interfaces like
            <classname>ActionListener</classname> inside a BeanShell script is
            one of the more powerful features of the BeanShell package. this
            technique is discussed in the next chapter; see <xref
            linkend="macro-tips-BeanShell-class" />.</para>
        </sect2>

        <sect2 id="explain-process-text">
            <title>Get the User's Input</title>

            <informalexample>
                <programlisting>// this is where the work gets done to insert
// the prefix and suffix
void processText()
{
    prefix = prefixField.getText();
    suffix = suffixField.getText();
    if(prefix.length() == 0 &amp;&amp; suffix.length() == 0)
        return;
    prefixField.addCurrentToHistory();
    suffixField.addCurrentToHistory();</programlisting>
            </informalexample>

            <para>The method <function>processText()</function> does the work of
            our macro. First we obtain the input from the two text fields with a
            call to their <function>getText()</function> methods. If they are
            both empty, there is nothing to do, so the method returns. If there
            is input, any text in the field is added to that field's stored
            history list by calling <function>addCurrentToHistory()</function>.
            We do not need to test the <varname>prefixField</varname> or
            <varname>suffixField</varname> controls for
            <constant>null</constant> or empty values because
            <function>addCurrentToHistory()</function> does that
            internally.</para>
        </sect2>

        <sect2 id="explain-jedit-calls">
            <title>Call jEdit Methods to Manipulate Text</title>

            <informalexample>
                <programlisting>    // text manipulation begins here using calls
    // to jEdit methods
    buffer.beginCompoundEdit();
    selectedLines = textArea.getSelectedLines();
    for(i = 0; i &lt; selectedLines.length; ++i)
    {
        offsetBOL = textArea.getLineStartOffset(
            selectedLines[i]);
        textArea.setCaretPosition(offsetBOL);
        textArea.goToStartOfWhiteSpace(false);
        textArea.goToEndOfWhiteSpace(true);
        text = textArea.getSelectedText();
        if(text == null) text = "";
        textArea.setSelectedText(prefix + text + suffix);
    }
    buffer.endCompoundEdit();
}</programlisting>
            </informalexample>

            <para>The text manipulation routine loops through each selected line
            in the text buffer. We get the loop parameters by calling
            <function>textArea.getSelectedLines()</function>, which returns an
            array consisting of the line numbers of every selected line. The
            array includes the number of the current line, whether or not it is
            selected, and the line numbers are sorted in increasing order. We
            iterate through each member of the <varname>selectedLines</varname>
            array, which represents the number of a selected line, and apply the
            following routine:</para>

            <itemizedlist>
                <listitem>
                    <para>Get the buffer position of the start of the line
                    (expressed as a zero-based index from the start of the
                    buffer) by calling
                    <function>textArea.getLineStartOffset(selectedLines[i])</function>;</para>
                </listitem>

                <listitem>
                    <para>Move the caret to that position by calling
                    <function>textArea.setCaretPosition()</function>;</para>
                </listitem>

                <listitem>
                    <para>Find the first and last non-whitespace characters on
                    the line by calling
                    <function>textArea.goToStartOfWhiteSpace()</function> and
                    <function>textArea.goToEndOfWhiteSpace()</function>;</para>

                    <para>The <function>goTo...</function> methods in <ulink
                    url="../api/org/gjt/sp/jedit/textarea/JEditTextArea.html">JEditTextArea</ulink>
                    take a single parameter which tells jEdit whether the text
                    between the current caret position and the desired position
                    should be selected. Here, we call
                    <function>textArea.goToStartOfWhiteSpace(false)</function>
                    so that no text is selected, then call
                    <function>textArea.goToEndOfWhiteSpace(true)</function> so
                    that all of the text between the beginning and ending
                    whitespace is selected.</para>
                </listitem>

                <listitem>
                    <para>Retrieve the selected text by storing the return value
                    of <function>textArea.getSelectedText()</function> in a new
                    variable <function>text</function>.</para>

                    <para>If the line is empty,
                    <function>getSelectedText()</function> will return
                    <constant>null</constant>. In that case, we assign an empty
                    string to <varname>text</varname> to avoid calling methods
                    on a null object.</para>
                </listitem>

                <listitem>
                    <para>Change the selected text to <varname>prefix + text +
                    suffix</varname> by calling
                    <function>textArea.setSelectedText()</function>. If there is
                    no selected text (for example, if the line is empty), the
                    prefix and suffix will be inserted without any intervening
                    characters.</para>
                </listitem>
            </itemizedlist>

            <sidebar>
                <title>Compound edits</title>

                <para>Note the <function>beginCompoundEdit()</function> and
                <function>endCompoundEdit()</function> calls. These ensure that
                all edits performed between the two calls can be undone in one
                step. Normally, jEdit automatically wraps a macro call in these
                methods; however if the macro shows a non-modal dialog box, as
                far as jEdit is concerned the macro has finished executing by
                the time the dialog is shown, since control returns to the event
                dispatch thread.</para>

                <para>If you do not understand this, don't worry; just keep it
                in mind if your macro needs to show a non-modal dialog box for
                some reason; Most macros won't.</para>
            </sidebar>

            <!-- <para>
    The loop routine is bracketed by calls to
    <function>buffer.beginCompoundEdit()</function> and
    <function>buffer.endCompoundEdit()</function>.  These methods
    modify the way in which jEdit's undo facility performs.  Text
    operations done between calls to these functions will be
    treated as a single operation for undo purposes.  A single undo
    command issued immediately after the macro completes will thus remove
    the prefix and suffix text from all of the previously selected lines.
  </para> -->
        </sect2>

        <sect2 id="explain-main">
            <title>The Main Routine</title>

            <informalexample>
                <programlisting>// this single line of code is the script's main routine
prefixSuffixDialog();</programlisting>
            </informalexample>

            <para>The call to <function>prefixSuffixDialog()</function>is the
            only line in the macro that is not inside an enclosing block.
            BeanShell treats such code as a top-level <function>main</function>
            method and begins execution with it.</para>

            <para>Our analysis of <filename>Add_Prefix_and_Suffix.bsh</filename>
            is now complete. In the next section, we look at other ways in which
            a macro can obtain user input, as well as other macro writing
            techniques.</para>
        </sect2>
    </sect1>
</chapter>