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18 years ago
Hi, I got tired of using a trace( $message, __FILE__, __LINE__ ) function I made.  It forced me to include the file and line params (since php doesn't have macros) so I decided to make an alternative.

Simply call this new version using trace( 'my message' ); and it prints out a stack trace in a clearer way than the one stored in the debug_backtrace() array.  It handles traces from outside of functions, traces in nested functions, and traces in included files, and also displays the function in a way that can be pasted right back into your php code for faster testing!

NOTE - be sure to save your files with the correct line endings for the line numbers to work correctly, which for Mac OS X is unix.  You can get to this option in the popup menu in the toolbar at the top of each window in BBEdit.

<?php

function    print_var( $var )
{
   if( is_string( $var ) )
       return( '"'.str_replace( array("\x00", "\x0a", "\x0d", "\x1a", "\x09"), array('\0', '\n', '\r', '\Z', '\t'), $var ).'"' );
   else if( is_bool( $var ) )
   {
       if( $var )
           return( 'true' );
       else
           return( 'false' );
   }
   else if( is_array( $var ) )
   {
       $result = 'array( ';
       $comma = '';
       foreach( $var as $key => $val )
       {
           $result .= $comma.print_var( $key ).' => '.print_var( $val );
           $comma = ', ';
       }
       $result .= ' )';
       return( $result );
   }
   
   return( var_export( $var, true ) );    // anything else, just let php try to print it
}

function    trace( $msg )
{
   echo "<pre>\n";
   
   //var_export( debug_backtrace() ); echo "</pre>\n"; return;    // this line shows what is going on underneath
   
   $trace = array_reverse( debug_backtrace() );
   $indent = '';
   $func = '';
   
   echo $msg."\n";
   
   foreach( $trace as $val)
   {
       echo $indent.$val['file'].' on line '.$val['line'];
       
       if( $func ) echo ' in function '.$func;
       
       if( $val['function'] == 'include' ||
           $val['function'] == 'require' ||
           $val['function'] == 'include_once' ||
           $val['function'] == 'require_once' )
           $func = '';
       else
       {
           $func = $val['function'].'(';
           
           if( isset( $val['args'][0] ) )
           {
               $func .= ' ';
               $comma = '';
               foreach( $val['args'] as $val )
               {
                   $func .= $comma.print_var( $val );
                   $comma = ', ';
               }
               $func .= ' ';
           }
           
           $func .= ')';
       }
       
       echo "\n";
       
       $indent .= "\t";
   }
   
   echo "</pre>\n";
}

trace( 'error outside function' );

function    test( $param1, $param2, $param3, $param4 )
{
   trace( 'error in test()' );
}

test( 1.1, "param2\n", array( 1 => "a\n", "b\n" => 2 ), false );

?>
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