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<html><head><title>B::Concise (Perl in a Nutshell, 2nd Edition)</title><link rel="stylesheet" type="text/css" href="../style/style1.css" /><meta name="DC.Creator" content="Stephen Spainhour" /><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="0596002416L" /><meta name="DC.Subject.Keyword" content="stuff" /><meta name="DC.Title" content="Perl in a Nutshell, 2nd Edition" /><meta name="DC.Type" content="Text.Monograph" /></head><body bgcolor="#ffffff"><img src="gifs/smbanner.gif" usemap="#banner-map" border="0" alt="Book Home" /><map name="banner-map"><area shape="rect" coords="1,-2,616,66" href="index.htm" alt="Java and XSLT" /><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="ch08_14.htm"><img src="../gifs/txtpreva.gif" alt="Previous" border="0" /></a></td><td align="center" valign="top" width="228" /><td align="right" valign="top" width="228"><a href="ch08_16.htm"><img src="../gifs/txtnexta.gif" alt="Next" border="0" /></a></td></tr></table></div><h2 class="sect1">8.15. B::Concise</h2><p><a name="INDEX-1292" />A module that walks the Perl syntax tree,printing concise info about the internal OPs of a Perlprogram's syntax tree. The format of the informationdisplayed is customizable. Its function is similar to that ofPerl's <em class="emphasis">-Dx</em> debugging flag orthe B::Terse module, but it is more sophisticated and flexible.Invoke as:</p><blockquote><pre class="code">perl -MO=Concise[,<em class="replaceable"><tt>options</em>] <em class="replaceable">program</tt></em></pre></blockquote><p><em class="replaceable"><tt>program</tt></em> is the name of the Perl script tocompile. Any non-option arguments are treated as the names of objectsto be saved; the main program is assumed if there are no extraarguments. Possible options are:</p><dl><dt><i><em class="emphasis">-basic</em></i></dt><dd>Prints OPs in the order they appear in the OP tree (a preordertraversal, starting at the root). Default.</p></dd><dt><i><em class="emphasis">-exec</em></i></dt><dd>Prints OPs in the order they would normally execute. For the majorityof constructs, this is a postorder traversal of the tree, ending atthe root.</p></dd><dt><i><em class="emphasis">-tree</em></i></dt><dd>Prints OPs in a text approximation of a tree, with the root of thetree at the left and"left-to-right" order of childrentransformed into "top-to-bottom".Unsuitable for large programs.</p></dd><dt><i><em class="emphasis">-compact</em></i></dt><dd>Uses a tree format in which the minimum amount of space is used forthe lines connecting nodes (one character in most cases).</p></dd><dt><i><em class="emphasis">-loose</em></i></dt><dd>Uses a tree format that uses longer edges to separate OP nodes.Default.</p></dd><dt><i><em class="emphasis">-vt</em></i></dt><dd>Uses tree-connecting characters drawn from the VT100 line-drawing set.</p></dd><dt><i><em class="emphasis">-ascii</em></i></dt><dd>Draws the tree with standard ASCII characters such as<tt class="literal">+</tt> and <tt class="literal">|</tt>. Default.</p></dd><dt><i><em class="emphasis">-main</em></i></dt><dd>Includes the main program in the output, even if subroutines werealso specified.</p></dd><dt><i><em class="emphasis">-basen</em></i></dt><dd>Prints OP sequence numbers in base n, with n <= 62. The default is36.</p></dd><dt><i><em class="emphasis">-bigendian</em></i></dt><dd>Prints sequence numbers with the most significant digit first.Default.</p></dd><dt><i><em class="emphasis">-littleendian</em></i></dt><dd>Prints sequence numbers with the least significant digit first.</p></dd><dt><i><em class="emphasis">-concise</em></i></dt><dd>Uses the author's favorite set of formattingconventions. Default.</p></dd><dt><i><em class="emphasis">-terse</em></i></dt><dd>Uses formatting conventions that emulate the output of B::Terse.</p></dd><dt><i><em class="emphasis">-linenoise</em></i></dt><dd>Uses formatting conventions in which the name of each OP, rather thanwritten out in full, is represented by a one- or two-characterabbreviation.</p></dd><dt><i><em class="emphasis">-debug</em></i></dt><dd>Uses formatting conventions reminiscient of B::Debug.</p></dd><dt><i><em class="emphasis">-env</em></i></dt><dd>Uses formatting conventions read from the environment variablesB_CONCISE_FORMAT, B_CONCISE_GOTO_FORMAT, and B_CONCISE_TREE_FORMAT.</p></dd></dl><hr width="684" align="left" /><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="ch08_14.htm"><img src="../gifs/txtpreva.gif" alt="Previous" border="0" /></a></td><td align="center" valign="top" width="228"><a href="index.htm"><img src="../gifs/txthome.gif" alt="Home" border="0" /></a></td><td align="right" valign="top" width="228"><a href="ch08_16.htm"><img src="../gifs/txtnexta.gif" alt="Next" border="0" /></a></td></tr><tr><td align="left" valign="top" width="228">8.14. B::CC</td><td align="center" valign="top" width="228"><a href="index/index.htm"><img src="../gifs/index.gif" alt="Book Index" border="0" /></a></td><td align="right" valign="top" width="228">8.16. B::Debug</td></tr></table></div><hr width="684" align="left" /><img src="../gifs/navbar.gif" usemap="#library-map" border="0" alt="Library Navigation Links" /><p><p><font size="-1"><a href="copyrght.htm">Copyright © 2002</a> O'Reilly & Associates. 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