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<pre>
<code style="font-family: Courier New, Courier, monospace; font-size: 12">
~/tcltk$ <b>tclsh</b>
% <b>set c1 {Bob Carol}</b>
Bob Carol

% <b>set c2 [list Ted Alice]</b>
Ted Alice

% <b>set Party1 [list $c1 $c2]</b>
{Bob Carol} {Ted Alice}

% <b>set Party2 [concat $c1 $c2]</b>
Bob Carol Ted Alice 

% <b>linsert $Party1 1 Richard</b>
{Bob Carol} Richard {Ted Alice}

%
			</code>
</pre>
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<td width="90%"><font size="4" face="Verdana, Arial, Helvetica"><b>Tcl lists</b></font></td><td width="200" align="right"><font size="1" face="Verdana, Arial, Helvetica"><nobr>   第 7 页（共15 页）</nobr></font></td>
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<p>Lists have two major uses in Tcl. The first we've already 
				seen demonstrated in the context of processing command 
				line arguments via the <i>foreach</i> command (found on
				<a href="l-tcl-3-5.html">Looping and branching in Tcl</a>). The second use 
				is to build up elements of a Tcl command dynamically, 
				which can be later executed by using the eval command, 
				as we see later in this tutorial.</p>
<p>The <i>list</i> command takes all of its arguments and 
				returns them in a list context. Arguments may be values 
				or variables. From the example at left, lists can be created 
				manually, or using list, which can take other lists as 
				arguments (thus saving the two couples orientation of our 
				first "Party"). Alternatively, the <i>concat</i> command is 
				used to merge two or more lists into a single entity of 
				top-level items, returning the second, more interesting 
				"Party".</p>
<p>Some other useful list commands and their syntax are:
			<ul>
<li>
<b>llength <i>$List</i></b> 
					- returns count of toplevel items.</li>
<li>
<b>lindex <i>$List n</i></b> - returns indexed item,
					counts from zero.</li>
<li>
<b>lrange <i>$List i j</i></b> - returns range of list elements.</li>
<li>
<b>lappend <i>$List item</i>...</b> - append items to list.</li>
<li>
<b>linsert <i>$List n item</i>...</b> - inserts item(s) at 
					the specified position in the list, moving other items down
					the list.</li>
</ul>
</p>
<p>The balance of list commands include <i>lreplace</i>, <i>lsearch</i>,  
				and <i>lsort</i>. The <i>split</i> command takes a string as input 
				and generates a properly parsed list, breaking the string at the 
				specified character. <i>join</i> performs the complementary 
				operation, taking list elements and stringing them together, 
				separated by a <i>joinstring</i>.</p>
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