Add missing opposite hints

src/voku/helper/UTF8.php

@@ -816,6 +816,8 @@
     /**
      * Get hexadecimal code point (U+xxxx) of a UTF-8 encoded character.
      *
+     * INFO: opposite to UTF8::hex_to_chr()
+     *
      * EXAMPLE: <code>UTF8::chr_to_hex('§'); // U+00a7</code>
      *
      * @param int|string $char   <p>The input character</p>
@@ -1218,7 +1220,7 @@
     /**
      * Converts an int value into a UTF-8 character.
      *
-     * INFO: opposite to UTF8::string()
+     * INFO: opposite to UTF8::chr_to_decimal()
      *
      * EXAMPLE: <code>UTF8::decimal_to_chr(931); // 'Σ'</code>
      *
@@ -2872,7 +2874,7 @@
     /**
      * Converts a UTF-8 string to a series of HTML numbered entities.
      *
-     * INFO: opposite to UTF8::html_decode()
+     * INFO: opposite to UTF8::html_entity_decode()
      *
      * EXAMPLE: <code>UTF8::html_encode('中文空白'); // '&#20013;&#25991;&#31354;&#30333;'</code>
      *
@@ -6964,11 +6966,11 @@
 
         $encoding = self::normalize_encoding($encoding, 'UTF-8');
 
         if ((int) self::strlen_in_byte($str, $encoding) <= $length) {
             return $str;
         }
 
         return ((string) self::substr_in_byte($str, 0, $length - (int) self::strlen_in_byte($str_add_on), $encoding)) . $str_add_on;
     }
 
     /**
@@ -9031,6 +9033,8 @@
     /**
      * Get a binary representation of a specific string.
      *
+     * INFO: opposite to UTF8::binary_to_str()
+     *
      * EXAPLE: <code>UTF8::str_to_binary('😃'); // '11110000100111111001100010000011'</code>
      *
      * @param string $str <p>The input string.</p>
@@ -9494,7 +9498,7 @@
             \Normalizer::normalize($str2, \Normalizer::NFD)
         );
 
         if (!is_int($cmp)) {
             return $cmp < 0 ? -1 : ($cmp > 0 ? 1 : 0);
         }
 
@@ -10272,7 +10276,7 @@
         $needle = (string) $needle;
 
         if ($haystack === '') {
             if (\PHP_VERSION_ID >= 80000 && $needle === '') {
                 return 0;
             }
 
@@ -10782,7 +10786,7 @@
         $needle = (string) $needle;
 
         if ($haystack === '') {
             if (\PHP_VERSION_ID >= 80000 && $needle === '') {
                 return 0;
             }
 
@@ -10954,7 +10958,7 @@
         $needle = (string) $needle;
 
         if ($haystack === '') {
             if (\PHP_VERSION_ID >= 80000 && $needle === '') {
                 return 0;
             }