#! /usr/bin/perl

# A script to scan PCRE's man pages to check for typos in the control

# sequences. I use only a small set of the available repertoire, so it is 

# straightforward to check that nothing else has slipped in by mistake. This

# script should be called in the doc directory.

$yield = 0;

while (scalar(@ARGV) > 0)

  {

  $line = 0; 

  $file = shift @ARGV;

  open (IN, $file) || die "Failed to open $file\n";

  while (<IN>)

    {  

    $line++; 

    if (/^\s*$/)

      {

      printf "Empty line $line of $file\n";

      $yield = 1;  

      }   

    elsif (/^\./)

      {

      if (!/^\.\s*$|

            ^\.B\s+\S| 

            ^\.TH\s\S|

            ^\.SH\s\S|

            ^\.SS\s\S|

            ^\.TP(?:\s\d+)?\s*$|

            ^\.ti\s\S| 

            ^\.SM\s*$|

            ^\.rs\s*$| 

            ^\.sp\s*$| 

            ^\.nf\s*$| 

            ^\.fi\s*$| 

            ^\.P\s*$| 

            ^\.PP\s*$| 

            ^\.\\"(?:\ HREF)?\s*$|

            ^\.\\"\sHTML\s<a\shref="[^"]+?">\s*$|

            ^\.\\"\sHTML\s<a\sname="[^"]+?"><\/a>\s*$|

            ^\.\\"\s<\/a>\s*$|

            ^\.\\"\sJOINSH\s*$|

            ^\.\\"\sJOIN\s*$/x  

         )

        {

        printf "Bad control line $line of $file\n";

        $yield = 1;

        }

      }

    else

      {

      if (/\\[^ef]|\\f[^IBP]/)

        {

        printf "Bad backslash in line $line of $file\n";  

        $yield = 1; 

        } 

      }   

    }

  close(IN);   

  }

exit $yield;

# End