[PHP-NOTES] note 130538 added to function.strrpos

An example function to show how to iterate through all matches in reverse order:  
<?php

function str_positions_reverse( $haystack, $needle, $fn = null ){
  if( $fn === null )  $positions = array();
  $needlen = strlen( $needle );
  $offset  = strlen( $haystack ) + $needlen;
  $pos     = strrpos( $haystack, $needle );
  while( $pos !== false ){
    if( $fn === null )  $positions[] = $pos;
    else if( null !== ( $r = $fn( $pos, $haystack, $needle )))  return $r;
    if( $pos < $needlen )  break;
    $pos = strrpos( $haystack, $needle, $pos - $offset );
  }
  if( $fn === null )  return $positions;
}

echo implode(',', str_positions_reverse('111111',  '11'));  // 4,2,0
echo implode(',', str_positions_reverse('1111111', '11'));  // 5,3,1

$path = '/Users//'.get_current_user().'/./Desktop/path/to/a/file.txt';
echo $path; // /Users//alfred.e.neumann/./Desktop/path/to/a/file.txt

echo 'slashes: ', implode(',', str_positions_reverse( $path, '/'));
// slashes: 44,42,39,34,26,24,7,6,0

echo "\nclosest real file: ", str_positions_reverse( $path, '/', function( $pos, $path ){
  $path = realpath( substr( $path, 0, $pos ));
  if( $path !== false )  return $path;
});
// closest real file: /Users/alfred.e.neumann/Desktop
?>
----
Server IP: 45.112.84.4
Probable Submitter: 80.90.5.137 (proxied: 188.143.70.42)
----
Manual Page -- https://php.net/manual/en/function.strrpos.php
Edit        -- https://main.php.net/note/edit/130538
Del: integrated  -- https://main.php.net/note/delete/130538/integrated
Del: useless     -- https://main.php.net/note/delete/130538/useless
Del: bad code    -- https://main.php.net/note/delete/130538/bad+code
Del: spam        -- https://main.php.net/note/delete/130538/spam
Del: non-english -- https://main.php.net/note/delete/130538/non-english
Del: in docs     -- https://main.php.net/note/delete/130538/in+docs
Del: other reasons-- https://main.php.net/note/delete/130538
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