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   13 
   14 <ul id="index">
   15   <li><a href="#NAME">NAME</a></li>
   16   <li><a href="#SYNOPSIS">SYNOPSIS</a></li>
   17   <li><a href="#DESCRIPTION">DESCRIPTION</a></li>
   18   <li><a href="#ERROR-HANDLING">ERROR HANDLING</a></li>
   19   <li><a href="#NOTES-ON-FORMATTING-PARAMETERS">NOTES ON FORMATTING PARAMETERS</a></li>
   20   <li><a href="#EXAMPLES">EXAMPLES</a></li>
   21   <li><a href="#Using-the-formatter-Callback-Object">Using the formatter Callback Object</a></li>
   22   <li><a href="#EXPORT">EXPORT</a></li>
   23   <li><a href="#INSTALLATION">INSTALLATION</a></li>
   24   <li><a href="#VERSION">VERSION</a></li>
   25   <li><a href="#LICENSE">LICENSE</a></li>
   26   <li><a href="#BUG-REPORTS">BUG REPORTS</a></li>
   27   <li><a href="#SEE-ALSO">SEE ALSO</a></li>
   28 </ul>
   29 
   30 <h1 id="NAME">NAME</h1>
   31 
   32 <p>Perl::Tidy - Parses and beautifies perl source</p>
   33 
   34 <h1 id="SYNOPSIS">SYNOPSIS</h1>
   35 
   36 <pre><code>    use Perl::Tidy;
   37 
   38     my $error_flag = Perl::Tidy::perltidy(
   39         source            =&gt; $source,
   40         destination       =&gt; $destination,
   41         stderr            =&gt; $stderr,
   42         argv              =&gt; $argv,
   43         perltidyrc        =&gt; $perltidyrc,
   44         logfile           =&gt; $logfile,
   45         errorfile         =&gt; $errorfile,
   46         formatter         =&gt; $formatter,           # callback object (see below)
   47         dump_options      =&gt; $dump_options,
   48         dump_options_type =&gt; $dump_options_type,
   49         prefilter         =&gt; $prefilter_coderef,
   50         postfilter        =&gt; $postfilter_coderef,
   51     );</code></pre>
   52 
   53 <h1 id="DESCRIPTION">DESCRIPTION</h1>
   54 
   55 <p>This module makes the functionality of the perltidy utility available to perl scripts. Any or all of the input parameters may be omitted, in which case the @ARGV array will be used to provide input parameters as described in the perltidy(1) man page.</p>
   56 
   57 <p>For example, the perltidy script is basically just this:</p>
   58 
   59 <pre><code>    use Perl::Tidy;
   60     Perl::Tidy::perltidy();</code></pre>
   61 
   62 <p>The call to <b>perltidy</b> returns a scalar <b>$error_flag</b> which is TRUE if an error caused premature termination, and FALSE if the process ran to normal completion. Additional discuss of errors is contained below in the <a href="#ERROR-HANDLING">&quot;ERROR HANDLING&quot;</a> section.</p>
   63 
   64 <p>The module accepts input and output streams by a variety of methods. The following list of parameters may be any of the following: a filename, an ARRAY reference, a SCALAR reference, or an object with either a <b>getline</b> or <b>print</b> method, as appropriate.</p>
   65 
   66 <pre><code>        source            - the source of the script to be formatted
   67         destination       - the destination of the formatted output
   68         stderr            - standard error output
   69         perltidyrc        - the .perltidyrc file
   70         logfile           - the .LOG file stream, if any 
   71         errorfile         - the .ERR file stream, if any
   72         dump_options      - ref to a hash to receive parameters (see below), 
   73         dump_options_type - controls contents of dump_options
   74         dump_getopt_flags - ref to a hash to receive Getopt flags
   75         dump_options_category - ref to a hash giving category of options
   76         dump_abbreviations    - ref to a hash giving all abbreviations</code></pre>
   77 
   78 <p>The following chart illustrates the logic used to decide how to treat a parameter.</p>
   79 
   80 <pre><code>   ref($param)  $param is assumed to be:
   81    -----------  ---------------------
   82    undef        a filename
   83    SCALAR       ref to string
   84    ARRAY        ref to array
   85    (other)      object with getline (if source) or print method</code></pre>
   86 
   87 <p>If the parameter is an object, and the object has a <b>close</b> method, that close method will be called at the end of the stream.</p>
   88 
   89 <dl>
   90 
   91 <dt id="source">source</dt>
   92 <dd>
   93 
   94 <p>If the <b>source</b> parameter is given, it defines the source of the input stream. If an input stream is defined with the <b>source</b> parameter then no other source filenames may be specified in the @ARGV array or <b>argv</b> parameter.</p>
   95 
   96 </dd>
   97 <dt id="destination">destination</dt>
   98 <dd>
   99 
  100 <p>If the <b>destination</b> parameter is given, it will be used to define the file or memory location to receive output of perltidy.</p>
  101 
  102 </dd>
  103 <dt id="stderr">stderr</dt>
  104 <dd>
  105 
  106 <p>The <b>stderr</b> parameter allows the calling program to redirect the stream that would otherwise go to the standard error output device to any of the stream types listed above. This stream contains important warnings and errors related to the parameters passed to perltidy.</p>
  107 
  108 </dd>
  109 <dt id="perltidyrc">perltidyrc</dt>
  110 <dd>
  111 
  112 <p>If the <b>perltidyrc</b> file is given, it will be used instead of any <i>.perltidyrc</i> configuration file that would otherwise be used.</p>
  113 
  114 </dd>
  115 <dt id="errorfile">errorfile</dt>
  116 <dd>
  117 
  118 <p>The <b>errorfile</b> parameter allows the calling program to capture the stream that would otherwise go to either a .ERR file. This stream contains warnings or errors related to the contents of one source file or stream.</p>
  119 
  120 <p>The reason that this is different from the stderr stream is that when perltidy is called to process multiple files there will be up to one .ERR file created for each file and it would be very confusing if they were combined.</p>
  121 
  122 <p>However if perltidy is called to process just a single perl script then it may be more convenient to combine the <b>errorfile</b> stream with the <b>stderr</b> stream. This can be done by setting the <b>-se</b> parameter, in which case this parameter is ignored.</p>
  123 
  124 </dd>
  125 <dt id="logfile">logfile</dt>
  126 <dd>
  127 
  128 <p>The <b>logfile</b> parameter allows the calling program to capture the log stream. This stream is only created if requested with a <b>-g</b> parameter. It contains detailed diagnostic information about a script which may be useful for debugging.</p>
  129 
  130 </dd>
  131 <dt id="argv">argv</dt>
  132 <dd>
  133 
  134 <p>If the <b>argv</b> parameter is given, it will be used instead of the <b>@ARGV</b> array. The <b>argv</b> parameter may be a string, a reference to a string, or a reference to an array. If it is a string or reference to a string, it will be parsed into an array of items just as if it were a command line string.</p>
  135 
  136 </dd>
  137 <dt id="dump_options">dump_options</dt>
  138 <dd>
  139 
  140 <p>If the <b>dump_options</b> parameter is given, it must be the reference to a hash. In this case, the parameters contained in any perltidyrc configuration file will be placed in this hash and perltidy will return immediately. This is equivalent to running perltidy with --dump-options, except that the parameters are returned in a hash rather than dumped to standard output. Also, by default only the parameters in the perltidyrc file are returned, but this can be changed (see the next parameter). This parameter provides a convenient method for external programs to read a perltidyrc file. An example program using this feature, <i>perltidyrc_dump.pl</i>, is included in the distribution.</p>
  141 
  142 <p>Any combination of the <b>dump_</b> parameters may be used together.</p>
  143 
  144 </dd>
  145 <dt id="dump_options_type">dump_options_type</dt>
  146 <dd>
  147 
  148 <p>This parameter is a string which can be used to control the parameters placed in the hash reference supplied by <b>dump_options</b>. The possible values are &#39;perltidyrc&#39; (default) and &#39;full&#39;. The &#39;full&#39; parameter causes both the default options plus any options found in a perltidyrc file to be returned.</p>
  149 
  150 </dd>
  151 <dt id="dump_getopt_flags">dump_getopt_flags</dt>
  152 <dd>
  153 
  154 <p>If the <b>dump_getopt_flags</b> parameter is given, it must be the reference to a hash. This hash will receive all of the parameters that perltidy understands and flags that are passed to Getopt::Long. This parameter may be used alone or with the <b>dump_options</b> flag. Perltidy will exit immediately after filling this hash. See the demo program <i>perltidyrc_dump.pl</i> for example usage.</p>
  155 
  156 </dd>
  157 <dt id="dump_options_category">dump_options_category</dt>
  158 <dd>
  159 
  160 <p>If the <b>dump_options_category</b> parameter is given, it must be the reference to a hash. This hash will receive a hash with keys equal to all long parameter names and values equal to the title of the corresponding section of the perltidy manual. See the demo program <i>perltidyrc_dump.pl</i> for example usage.</p>
  161 
  162 </dd>
  163 <dt id="dump_abbreviations">dump_abbreviations</dt>
  164 <dd>
  165 
  166 <p>If the <b>dump_abbreviations</b> parameter is given, it must be the reference to a hash. This hash will receive all abbreviations used by Perl::Tidy. See the demo program <i>perltidyrc_dump.pl</i> for example usage.</p>
  167 
  168 </dd>
  169 <dt id="prefilter">prefilter</dt>
  170 <dd>
  171 
  172 <p>A code reference that will be applied to the source before tidying. It is expected to take the full content as a string in its input, and output the transformed content.</p>
  173 
  174 </dd>
  175 <dt id="postfilter">postfilter</dt>
  176 <dd>
  177 
  178 <p>A code reference that will be applied to the tidied result before outputting. It is expected to take the full content as a string in its input, and output the transformed content.</p>
  179 
  180 <p>Note: A convenient way to check the function of your custom prefilter and postfilter code is to use the --notidy option, first with just the prefilter and then with both the prefilter and postfilter. See also the file <b>filter_example.pl</b> in the perltidy distribution.</p>
  181 
  182 </dd>
  183 </dl>
  184 
  185 <h1 id="ERROR-HANDLING">ERROR HANDLING</h1>
  186 
  187 <p>An exit value of 0, 1, or 2 is returned by perltidy to indicate the status of the result.</p>
  188 
  189 <p>A exit value of 0 indicates that perltidy ran to completion with no error messages.</p>
  190 
  191 <p>An exit value of 1 indicates that the process had to be terminated early due to errors in the input parameters. This can happen for example if a parameter is misspelled or given an invalid value. The calling program should check for this flag because if it is set the destination stream will be empty or incomplete and should be ignored. Error messages in the <b>stderr</b> stream will indicate the cause of any problem.</p>
  192 
  193 <p>An exit value of 2 indicates that perltidy ran to completion but there there are warning messages in the <b>stderr</b> stream related to parameter errors or conflicts and/or warning messages in the <b>errorfile</b> stream relating to possible syntax errors in the source code being tidied.</p>
  194 
  195 <p>In the event of a catastrophic error for which recovery is not possible <b>perltidy</b> terminates by making calls to <b>croak</b> or <b>confess</b> to help the programmer localize the problem. These should normally only occur during program development.</p>
  196 
  197 <h1 id="NOTES-ON-FORMATTING-PARAMETERS">NOTES ON FORMATTING PARAMETERS</h1>
  198 
  199 <p>Parameters which control formatting may be passed in several ways: in a <i>.perltidyrc</i> configuration file, in the <b>perltidyrc</b> parameter, and in the <b>argv</b> parameter.</p>
  200 
  201 <p>The <b>-syn</b> (<b>--check-syntax</b>) flag may be used with all source and destination streams except for standard input and output. However data streams which are not associated with a filename will be copied to a temporary file before being passed to Perl. This use of temporary files can cause somewhat confusing output from Perl.</p>
  202 
  203 <p>If the <b>-pbp</b> style is used it will typically be necessary to also specify a <b>-nst</b> flag. This is necessary to turn off the <b>-st</b> flag contained in the <b>-pbp</b> parameter set which otherwise would direct the output stream to the standard output.</p>
  204 
  205 <h1 id="EXAMPLES">EXAMPLES</h1>
  206 
  207 <p>The following example uses string references to hold the input and output code and error streams, and illustrates checking for errors.</p>
  208 
  209 <pre><code>  use Perl::Tidy;
  210   
  211   my $source_string = &lt;&lt;&#39;EOT&#39;;
  212   my$error=Perl::Tidy::perltidy(argv=&gt;$argv,source=&gt;\$source_string,
  213     destination=&gt;\$dest_string,stderr=&gt;\$stderr_string,
  214   errorfile=&gt;\$errorfile_string,);
  215   EOT
  216   
  217   my $dest_string;
  218   my $stderr_string;
  219   my $errorfile_string;
  220   my $argv = &quot;-npro&quot;;   # Ignore any .perltidyrc at this site
  221   $argv .= &quot; -pbp&quot;;     # Format according to perl best practices
  222   $argv .= &quot; -nst&quot;;     # Must turn off -st in case -pbp is specified
  223   $argv .= &quot; -se&quot;;      # -se appends the errorfile to stderr
  224   ## $argv .= &quot; --spell-check&quot;;  # uncomment to trigger an error
  225   
  226   print &quot;&lt;&lt;RAW SOURCE&gt;&gt;\n$source_string\n&quot;;
  227   
  228   my $error = Perl::Tidy::perltidy(
  229       argv        =&gt; $argv,
  230       source      =&gt; \$source_string,
  231       destination =&gt; \$dest_string,
  232       stderr      =&gt; \$stderr_string,
  233       errorfile   =&gt; \$errorfile_string,    # ignored when -se flag is set
  234       ##phasers   =&gt; &#39;stun&#39;,                # uncomment to trigger an error
  235   );
  236   
  237   if ($error) {
  238   
  239       # serious error in input parameters, no tidied output
  240       print &quot;&lt;&lt;STDERR&gt;&gt;\n$stderr_string\n&quot;;
  241       die &quot;Exiting because of serious errors\n&quot;;
  242   }
  243   
  244   if ($dest_string)      { print &quot;&lt;&lt;TIDIED SOURCE&gt;&gt;\n$dest_string\n&quot; }
  245   if ($stderr_string)    { print &quot;&lt;&lt;STDERR&gt;&gt;\n$stderr_string\n&quot; }
  246   if ($errorfile_string) { print &quot;&lt;&lt;.ERR file&gt;&gt;\n$errorfile_string\n&quot; }</code></pre>
  247 
  248 <p>Additional examples are given in examples section of the perltidy distribution.</p>
  249 
  250 <h1 id="Using-the-formatter-Callback-Object">Using the <b>formatter</b> Callback Object</h1>
  251 
  252 <p>The <b>formatter</b> parameter is an optional callback object which allows the calling program to receive tokenized lines directly from perltidy for further specialized processing. When this parameter is used, the two formatting options which are built into perltidy (beautification or html) are ignored. The following diagram illustrates the logical flow:</p>
  253 
  254 <pre><code>                    |-- (normal route)   -&gt; code beautification
  255   caller-&gt;perltidy-&gt;|-- (-html flag )    -&gt; create html 
  256                     |-- (formatter given)-&gt; callback to write_line</code></pre>
  257 
  258 <p>This can be useful for processing perl scripts in some way. The parameter <code>$formatter</code> in the perltidy call,</p>
  259 
  260 <pre><code>        formatter   =&gt; $formatter,  </code></pre>
  261 
  262 <p>is an object created by the caller with a <code>write_line</code> method which will accept and process tokenized lines, one line per call. Here is a simple example of a <code>write_line</code> which merely prints the line number, the line type (as determined by perltidy), and the text of the line:</p>
  263 
  264 <pre><code> sub write_line {
  265  
  266      # This is called from perltidy line-by-line
  267      my $self              = shift;
  268      my $line_of_tokens    = shift;
  269      my $line_type         = $line_of_tokens-&gt;{_line_type};
  270      my $input_line_number = $line_of_tokens-&gt;{_line_number};
  271      my $input_line        = $line_of_tokens-&gt;{_line_text};
  272      print &quot;$input_line_number:$line_type:$input_line&quot;;
  273  }</code></pre>
  274 
  275 <p>The complete program, <b>perllinetype</b>, is contained in the examples section of the source distribution. As this example shows, the callback method receives a parameter <b>$line_of_tokens</b>, which is a reference to a hash of other useful information. This example uses these hash entries:</p>
  276 
  277 <pre><code> $line_of_tokens-&gt;{_line_number} - the line number (1,2,...)
  278  $line_of_tokens-&gt;{_line_text}   - the text of the line
  279  $line_of_tokens-&gt;{_line_type}   - the type of the line, one of:
  280 
  281     SYSTEM         - system-specific code before hash-bang line
  282     CODE           - line of perl code (including comments)
  283     POD_START      - line starting pod, such as &#39;=head&#39;
  284     POD            - pod documentation text
  285     POD_END        - last line of pod section, &#39;=cut&#39;
  286     HERE           - text of here-document
  287     HERE_END       - last line of here-doc (target word)
  288     FORMAT         - format section
  289     FORMAT_END     - last line of format section, &#39;.&#39;
  290     DATA_START     - __DATA__ line
  291     DATA           - unidentified text following __DATA__
  292     END_START      - __END__ line
  293     END            - unidentified text following __END__
  294     ERROR          - we are in big trouble, probably not a perl script</code></pre>
  295 
  296 <p>Most applications will be only interested in lines of type <b>CODE</b>. For another example, let&#39;s write a program which checks for one of the so-called <i>naughty matching variables</i> <code>&amp;`</code>, <code>$&amp;</code>, and <code>$&#39;</code>, which can slow down processing. Here is a <b>write_line</b>, from the example program <b>find_naughty.pl</b>, which does that:</p>
  297 
  298 <pre><code> sub write_line {
  299  
  300      # This is called back from perltidy line-by-line
  301      # We&#39;re looking for $`, $&amp;, and $&#39;
  302      my ( $self, $line_of_tokens ) = @_;
  303  
  304      # pull out some stuff we might need
  305      my $line_type         = $line_of_tokens-&gt;{_line_type};
  306      my $input_line_number = $line_of_tokens-&gt;{_line_number};
  307      my $input_line        = $line_of_tokens-&gt;{_line_text};
  308      my $rtoken_type       = $line_of_tokens-&gt;{_rtoken_type};
  309      my $rtokens           = $line_of_tokens-&gt;{_rtokens};
  310      chomp $input_line;
  311  
  312      # skip comments, pod, etc
  313      return if ( $line_type ne &#39;CODE&#39; );
  314  
  315      # loop over tokens looking for $`, $&amp;, and $&#39;
  316      for ( my $j = 0 ; $j &lt; @$rtoken_type ; $j++ ) {
  317  
  318          # we only want to examine token types &#39;i&#39; (identifier)
  319          next unless $$rtoken_type[$j] eq &#39;i&#39;;
  320  
  321          # pull out the actual token text
  322          my $token = $$rtokens[$j];
  323  
  324          # and check it
  325          if ( $token =~ /^\$[\`\&amp;\&#39;]$/ ) {
  326              print STDERR
  327                &quot;$input_line_number: $token\n&quot;;
  328          }
  329      }
  330  }</code></pre>
  331 
  332 <p>This example pulls out these tokenization variables from the $line_of_tokens hash reference:</p>
  333 
  334 <pre><code>     $rtoken_type = $line_of_tokens-&gt;{_rtoken_type};
  335      $rtokens     = $line_of_tokens-&gt;{_rtokens};</code></pre>
  336 
  337 <p>The variable <code>$rtoken_type</code> is a reference to an array of token type codes, and <code>$rtokens</code> is a reference to a corresponding array of token text. These are obviously only defined for lines of type <b>CODE</b>. Perltidy classifies tokens into types, and has a brief code for each type. You can get a complete list at any time by running perltidy from the command line with</p>
  338 
  339 <pre><code>     perltidy --dump-token-types</code></pre>
  340 
  341 <p>In the present example, we are only looking for tokens of type <b>i</b> (identifiers), so the for loop skips past all other types. When an identifier is found, its actual text is checked to see if it is one being sought. If so, the above write_line prints the token and its line number.</p>
  342 
  343 <p>The <b>formatter</b> feature is relatively new in perltidy, and further documentation needs to be written to complete its description. However, several example programs have been written and can be found in the <b>examples</b> section of the source distribution. Probably the best way to get started is to find one of the examples which most closely matches your application and start modifying it.</p>
  344 
  345 <p>For help with perltidy&#39;s peculiar way of breaking lines into tokens, you might run, from the command line,</p>
  346 
  347 <pre><code> perltidy -D filename</code></pre>
  348 
  349 <p>where <i>filename</i> is a short script of interest. This will produce <i>filename.DEBUG</i> with interleaved lines of text and their token types. The <b>-D</b> flag has been in perltidy from the beginning for this purpose. If you want to see the code which creates this file, it is <code>write_debug_entry</code> in Tidy.pm.</p>
  350 
  351 <h1 id="EXPORT">EXPORT</h1>
  352 
  353 <pre><code>  &amp;perltidy</code></pre>
  354 
  355 <h1 id="INSTALLATION">INSTALLATION</h1>
  356 
  357 <p>The module &#39;Perl::Tidy&#39; comes with a binary &#39;perltidy&#39; which is installed when the module is installed. The module name is case-sensitive. For example, the basic command for installing with cpanm is &#39;cpanm Perl::Tidy&#39;.</p>
  358 
  359 <h1 id="VERSION">VERSION</h1>
  360 
  361 <p>This man page documents Perl::Tidy version 20200110</p>
  362 
  363 <h1 id="LICENSE">LICENSE</h1>
  364 
  365 <p>This package is free software; you can redistribute it and/or modify it under the terms of the &quot;GNU General Public License&quot;.</p>
  366 
  367 <p>Please refer to the file &quot;COPYING&quot; for details.</p>
  368 
  369 <h1 id="BUG-REPORTS">BUG REPORTS</h1>
  370 
  371 <p>A list of current bugs and issues can be found at the CPAN site <a href="https://rt.cpan.org/Public/Dist/Display.html?Name=Perl-Tidy">https://rt.cpan.org/Public/Dist/Display.html?Name=Perl-Tidy</a></p>
  372 
  373 <p>To report a new bug or problem, use the link on this page.</p>
  374 
  375 <p>The source code repository is at <a href="https://github.com/perltidy/perltidy">https://github.com/perltidy/perltidy</a>.</p>
  376 
  377 <h1 id="SEE-ALSO">SEE ALSO</h1>
  378 
  379 <p>The perltidy(1) man page describes all of the features of perltidy. It can be found at http://perltidy.sourceforge.net.</p>
  380 
  381 
  382 </body>
  383 
  384 </html>
  385 
  386