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<html><head><title>XML Processors (Perl and XML)</title><link rel="stylesheet" type="text/css" href="../style/style1.css" /><meta name="DC.Creator" content="Erik T. Ray and Jason McIntosh" /><meta name="DC.Format" content="text/xml" scheme="MIME" /><meta name="DC.Language" content="en-US" /><meta name="DC.Publisher" content="O'Reilly & Associates, Inc." /><meta name="DC.Source" scheme="ISBN" content="059600205XL" /><meta name="DC.Subject.Keyword" content="stuff" /><meta name="DC.Title" content="Perl and XML" /><meta name="DC.Type" content="Text.Monograph" /></head><body bgcolor="#ffffff"><img alt="Book Home" border="0" src="gifs/smbanner.gif" usemap="#banner-map" /><map name="banner-map"><area shape="rect" coords="1,-2,616,66" href="index.htm" alt="Perl & XML" /><area shape="rect" coords="629,-11,726,25" href="jobjects/fsearch.htm" alt="Search this book" /></map><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="ch01_02.htm"><img alt="Previous" border="0" src="../gifs/txtpreva.gif" /></a></td><td align="center" valign="top" width="228" /><td align="right" valign="top" width="228"><a href="ch01_04.htm"><img alt="Next" border="0" src="../gifs/txtnexta.gif" /></a></td></tr></table></div><h2 class="sect1">1.3. XML Processors</h2><p>Now that you see the easy side of XML, we will expose some ofXML's quirks. You need to consider these quirks whenworking with XML and Perl.</p><p>When we refer in this book to an <em class="emphasis">XMLprocessor</em><a name="INDEX-24" /> (which we'll often referto in shorthand as a <em class="emphasis">processor</em>, not to beconfused with the central processing unit of a computer system thathas the same nickname), we refer to software that can either read orgenerate XML documents. We use this term in the most generalway -- what the program actually <em class="emphasis">does</em> withthe content it might find in the XML it reads is not the concern ofthe processor itself, nor is it the processor'sresponsibility to determine the origin of the document or decide whatto do with one that is generated.</p><p>As you might expect, a raw XML processor working aloneisn't very interesting. For this reason, a computerprogram that actually does something cool or useful with XML uses aprocessor as just one component. It usually reads an XML file and,through the magic of parsing, turns it into in-memory structures thatthe rest of the program can do whatever it likes with.</p><p>In the Perl world, this behavior becomes possible through the use ofPerl modules: typically, a program that needs to process XMLembraces, through the <tt class="literal">use</tt> pragma, an existingpackage that makes a programmer interface available (usually anobject-oriented one). This is why, before they get down to business,many XML-handling Perl programs start out with <tt class="literal">useXML::Parser;</tt><a name="INDEX-25" /> or something similar. With one littleline, they're able to leave all the dirty work ofXML parsing to another, previously written module, leaving their owncode to decide what to do pre- and post-processing.</p><hr width="684" align="left" /><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="ch01_02.htm"><img alt="Previous" border="0" src="../gifs/txtpreva.gif" /></a></td><td align="center" valign="top" width="228"><a href="index.htm"><img alt="Home" border="0" src="../gifs/txthome.gif" /></a></td><td align="right" valign="top" width="228"><a href="ch01_04.htm"><img alt="Next" border="0" src="../gifs/txtnexta.gif" /></a></td></tr><tr><td align="left" valign="top" width="228">1.2. XML Is Simple with XML::Simple</td><td align="center" valign="top" width="228"><a href="index/index.htm"><img alt="Book Index" border="0" src="../gifs/index.gif" /></a></td><td align="right" valign="top" width="228">1.4. A Myriad of Modules</td></tr></table></div><hr width="684" align="left" /><img alt="Library Navigation Links" border="0" src="../gifs/navbar.gif" usemap="#library-map" /><p><p><font size="-1"><a href="copyrght.htm">Copyright © 2002</a> O'Reilly & Associates. All rights reserved.</font></p><map name="library-map"><area shape="rect" coords="1,0,85,94" href="../index.htm"><area shape="rect" coords="86,1,178,103" href="../lwp/index.htm"><area shape="rect" coords="180,0,265,103" href="../lperl/index.htm"><area shape="rect" coords="267,0,353,105" href="../perlnut/index.htm"><area shape="rect" coords="354,1,446,115" href="../prog/index.htm"><area shape="rect" coords="448,0,526,132" href="../tk/index.htm"><area shape="rect" coords="528,1,615,119" href="../cookbook/index.htm"><area shape="rect" coords="617,0,690,135" href="../pxml/index.htm"></map></body></html>⌨️ 快捷键说明
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