Unicode.php in Zircon Profile 8
Same filename and directory in other branches
Contains \Drupal\Component\Utility\Unicode.
Namespace
Drupal\Component\UtilityFile
core/lib/Drupal/Component/Utility/Unicode.phpView source
<?php
/**
* @file
* Contains \Drupal\Component\Utility\Unicode.
*/
namespace Drupal\Component\Utility;
/**
* Provides Unicode-related conversions and operations.
*
* @ingroup utility
*/
class Unicode {
/**
* Matches Unicode characters that are word boundaries.
*
* Characters with the following General_category (gc) property values are used
* as word boundaries. While this does not fully conform to the Word Boundaries
* algorithm described in http://unicode.org/reports/tr29, as PCRE does not
* contain the Word_Break property table, this simpler algorithm has to do.
* - Cc, Cf, Cn, Co, Cs: Other.
* - Pc, Pd, Pe, Pf, Pi, Po, Ps: Punctuation.
* - Sc, Sk, Sm, So: Symbols.
* - Zl, Zp, Zs: Separators.
*
* Non-boundary characters include the following General_category (gc) property
* values:
* - Ll, Lm, Lo, Lt, Lu: Letters.
* - Mc, Me, Mn: Combining Marks.
* - Nd, Nl, No: Numbers.
*
* Note that the PCRE property matcher is not used because we wanted to be
* compatible with Unicode 5.2.0 regardless of the PCRE version used (and any
* bugs in PCRE property tables).
*
* @see http://unicode.org/glossary
*/
const PREG_CLASS_WORD_BOUNDARY = <<<'EOD'
\x{0}-\x{2F}\x{3A}-\x{40}\x{5B}-\x{60}\x{7B}-\x{A9}\x{AB}-\x{B1}\x{B4}
\x{B6}-\x{B8}\x{BB}\x{BF}\x{D7}\x{F7}\x{2C2}-\x{2C5}\x{2D2}-\x{2DF}
\x{2E5}-\x{2EB}\x{2ED}\x{2EF}-\x{2FF}\x{375}\x{37E}-\x{385}\x{387}\x{3F6}
\x{482}\x{55A}-\x{55F}\x{589}-\x{58A}\x{5BE}\x{5C0}\x{5C3}\x{5C6}
\x{5F3}-\x{60F}\x{61B}-\x{61F}\x{66A}-\x{66D}\x{6D4}\x{6DD}\x{6E9}
\x{6FD}-\x{6FE}\x{700}-\x{70F}\x{7F6}-\x{7F9}\x{830}-\x{83E}
\x{964}-\x{965}\x{970}\x{9F2}-\x{9F3}\x{9FA}-\x{9FB}\x{AF1}\x{B70}
\x{BF3}-\x{BFA}\x{C7F}\x{CF1}-\x{CF2}\x{D79}\x{DF4}\x{E3F}\x{E4F}
\x{E5A}-\x{E5B}\x{F01}-\x{F17}\x{F1A}-\x{F1F}\x{F34}\x{F36}\x{F38}
\x{F3A}-\x{F3D}\x{F85}\x{FBE}-\x{FC5}\x{FC7}-\x{FD8}\x{104A}-\x{104F}
\x{109E}-\x{109F}\x{10FB}\x{1360}-\x{1368}\x{1390}-\x{1399}\x{1400}
\x{166D}-\x{166E}\x{1680}\x{169B}-\x{169C}\x{16EB}-\x{16ED}
\x{1735}-\x{1736}\x{17B4}-\x{17B5}\x{17D4}-\x{17D6}\x{17D8}-\x{17DB}
\x{1800}-\x{180A}\x{180E}\x{1940}-\x{1945}\x{19DE}-\x{19FF}
\x{1A1E}-\x{1A1F}\x{1AA0}-\x{1AA6}\x{1AA8}-\x{1AAD}\x{1B5A}-\x{1B6A}
\x{1B74}-\x{1B7C}\x{1C3B}-\x{1C3F}\x{1C7E}-\x{1C7F}\x{1CD3}\x{1FBD}
\x{1FBF}-\x{1FC1}\x{1FCD}-\x{1FCF}\x{1FDD}-\x{1FDF}\x{1FED}-\x{1FEF}
\x{1FFD}-\x{206F}\x{207A}-\x{207E}\x{208A}-\x{208E}\x{20A0}-\x{20B8}
\x{2100}-\x{2101}\x{2103}-\x{2106}\x{2108}-\x{2109}\x{2114}
\x{2116}-\x{2118}\x{211E}-\x{2123}\x{2125}\x{2127}\x{2129}\x{212E}
\x{213A}-\x{213B}\x{2140}-\x{2144}\x{214A}-\x{214D}\x{214F}
\x{2190}-\x{244A}\x{249C}-\x{24E9}\x{2500}-\x{2775}\x{2794}-\x{2B59}
\x{2CE5}-\x{2CEA}\x{2CF9}-\x{2CFC}\x{2CFE}-\x{2CFF}\x{2E00}-\x{2E2E}
\x{2E30}-\x{3004}\x{3008}-\x{3020}\x{3030}\x{3036}-\x{3037}
\x{303D}-\x{303F}\x{309B}-\x{309C}\x{30A0}\x{30FB}\x{3190}-\x{3191}
\x{3196}-\x{319F}\x{31C0}-\x{31E3}\x{3200}-\x{321E}\x{322A}-\x{3250}
\x{3260}-\x{327F}\x{328A}-\x{32B0}\x{32C0}-\x{33FF}\x{4DC0}-\x{4DFF}
\x{A490}-\x{A4C6}\x{A4FE}-\x{A4FF}\x{A60D}-\x{A60F}\x{A673}\x{A67E}
\x{A6F2}-\x{A716}\x{A720}-\x{A721}\x{A789}-\x{A78A}\x{A828}-\x{A82B}
\x{A836}-\x{A839}\x{A874}-\x{A877}\x{A8CE}-\x{A8CF}\x{A8F8}-\x{A8FA}
\x{A92E}-\x{A92F}\x{A95F}\x{A9C1}-\x{A9CD}\x{A9DE}-\x{A9DF}
\x{AA5C}-\x{AA5F}\x{AA77}-\x{AA79}\x{AADE}-\x{AADF}\x{ABEB}
\x{E000}-\x{F8FF}\x{FB29}\x{FD3E}-\x{FD3F}\x{FDFC}-\x{FDFD}
\x{FE10}-\x{FE19}\x{FE30}-\x{FE6B}\x{FEFF}-\x{FF0F}\x{FF1A}-\x{FF20}
\x{FF3B}-\x{FF40}\x{FF5B}-\x{FF65}\x{FFE0}-\x{FFFD}
EOD;
/**
* Indicates that standard PHP (emulated) unicode support is being used.
*/
const STATUS_SINGLEBYTE = 0;
/**
* Indicates that full unicode support with the PHP mbstring extension is
* being used.
*/
const STATUS_MULTIBYTE = 1;
/**
* Indicates an error during check for PHP unicode support.
*/
const STATUS_ERROR = -1;
/**
* Holds the multibyte capabilities of the current environment.
*
* @var int
*/
protected static $status = 0;
/**
* Gets the current status of unicode/multibyte support on this environment.
*
* @return int
* The status of multibyte support. It can be one of:
* - \Drupal\Component\Utility\Unicode::STATUS_MULTIBYTE
* Full unicode support using an extension.
* - \Drupal\Component\Utility\Unicode::STATUS_SINGLEBYTE
* Standard PHP (emulated) unicode support.
* - \Drupal\Component\Utility\Unicode::STATUS_ERROR
* An error occurred. No unicode support.
*/
public static function getStatus() {
return static::$status;
}
/**
* Sets the value for multibyte support status for the current environment.
*
* The following status keys are supported:
* - \Drupal\Component\Utility\Unicode::STATUS_MULTIBYTE
* Full unicode support using an extension.
* - \Drupal\Component\Utility\Unicode::STATUS_SINGLEBYTE
* Standard PHP (emulated) unicode support.
* - \Drupal\Component\Utility\Unicode::STATUS_ERROR
* An error occurred. No unicode support.
*
* @param int $status
* The new status of multibyte support.
*/
public static function setStatus($status) {
if (!in_array($status, array(
static::STATUS_SINGLEBYTE,
static::STATUS_MULTIBYTE,
static::STATUS_ERROR,
))) {
throw new \InvalidArgumentException('Invalid status value for unicode support.');
}
static::$status = $status;
}
/**
* Checks for Unicode support in PHP and sets the proper settings if possible.
*
* Because of the need to be able to handle text in various encodings, we do
* not support mbstring function overloading. HTTP input/output conversion
* must be disabled for similar reasons.
*
* @return string
* A string identifier of a failed multibyte extension check, if any.
* Otherwise, an empty string.
*/
public static function check() {
// Check for mbstring extension.
if (!function_exists('mb_strlen')) {
static::$status = static::STATUS_SINGLEBYTE;
return 'mb_strlen';
}
// Check mbstring configuration.
if (ini_get('mbstring.func_overload') != 0) {
static::$status = static::STATUS_ERROR;
return 'mbstring.func_overload';
}
if (ini_get('mbstring.encoding_translation') != 0) {
static::$status = static::STATUS_ERROR;
return 'mbstring.encoding_translation';
}
// mbstring.http_input and mbstring.http_output are deprecated and empty by
// default in PHP 5.6.
if (version_compare(PHP_VERSION, '5.6.0') == -1) {
if (ini_get('mbstring.http_input') != 'pass') {
static::$status = static::STATUS_ERROR;
return 'mbstring.http_input';
}
if (ini_get('mbstring.http_output') != 'pass') {
static::$status = static::STATUS_ERROR;
return 'mbstring.http_output';
}
}
// Set appropriate configuration.
mb_internal_encoding('utf-8');
mb_language('uni');
static::$status = static::STATUS_MULTIBYTE;
return '';
}
/**
* Decodes UTF byte-order mark (BOM) into the encoding's name.
*
* @param string $data
* The data possibly containing a BOM. This can be the entire contents of
* a file, or just a fragment containing at least the first five bytes.
*
* @return string|bool
* The name of the encoding, or FALSE if no byte order mark was present.
*/
public static function encodingFromBOM($data) {
static $bomMap = array(
"" => 'UTF-8',
"" => 'UTF-16BE',
"" => 'UTF-16LE',
"" => 'UTF-32BE',
"" => 'UTF-32LE',
"+/v8" => 'UTF-7',
"+/v9" => 'UTF-7',
"+/v+" => 'UTF-7',
"+/v/" => 'UTF-7',
"+/v8-" => 'UTF-7',
);
foreach ($bomMap as $bom => $encoding) {
if (strpos($data, $bom) === 0) {
return $encoding;
}
}
return FALSE;
}
/**
* Converts data to UTF-8.
*
* Requires the iconv, GNU recode or mbstring PHP extension.
*
* @param string $data
* The data to be converted.
* @param string $encoding
* The encoding that the data is in.
*
* @return string|bool
* Converted data or FALSE.
*/
public static function convertToUtf8($data, $encoding) {
if (function_exists('iconv')) {
return @iconv($encoding, 'utf-8', $data);
}
elseif (function_exists('mb_convert_encoding')) {
return @mb_convert_encoding($data, 'utf-8', $encoding);
}
elseif (function_exists('recode_string')) {
return @recode_string($encoding . '..utf-8', $data);
}
// Cannot convert.
return FALSE;
}
/**
* Truncates a UTF-8-encoded string safely to a number of bytes.
*
* If the end position is in the middle of a UTF-8 sequence, it scans backwards
* until the beginning of the byte sequence.
*
* Use this function whenever you want to chop off a string at an unsure
* location. On the other hand, if you're sure that you're splitting on a
* character boundary (e.g. after using strpos() or similar), you can safely
* use substr() instead.
*
* @param string $string
* The string to truncate.
* @param int $len
* An upper limit on the returned string length.
*
* @return string
* The truncated string.
*/
public static function truncateBytes($string, $len) {
if (strlen($string) <= $len) {
return $string;
}
if (ord($string[$len]) < 0x80 || ord($string[$len]) >= 0xc0) {
return substr($string, 0, $len);
}
// Scan backwards to beginning of the byte sequence.
while (--$len >= 0 && ord($string[$len]) >= 0x80 && ord($string[$len]) < 0xc0) {
}
return substr($string, 0, $len);
}
/**
* Counts the number of characters in a UTF-8 string.
*
* This is less than or equal to the byte count.
*
* @param string $text
* The string to run the operation on.
*
* @return int
* The length of the string.
*/
public static function strlen($text) {
if (static::getStatus() == static::STATUS_MULTIBYTE) {
return mb_strlen($text);
}
else {
// Do not count UTF-8 continuation bytes.
return strlen(preg_replace("", '', $text));
}
}
/**
* Converts a UTF-8 string to uppercase.
*
* @param string $text
* The string to run the operation on.
*
* @return string
* The string in uppercase.
*/
public static function strtoupper($text) {
if (static::getStatus() == static::STATUS_MULTIBYTE) {
return mb_strtoupper($text);
}
else {
// Use C-locale for ASCII-only uppercase.
$text = strtoupper($text);
// Case flip Latin-1 accented letters.
$text = preg_replace_callback('/\\xC3[\\xA0-\\xB6\\xB8-\\xBE]/', '\\Drupal\\Component\\Utility\\Unicode::caseFlip', $text);
return $text;
}
}
/**
* Converts a UTF-8 string to lowercase.
*
* @param string $text
* The string to run the operation on.
*
* @return string
* The string in lowercase.
*/
public static function strtolower($text) {
if (static::getStatus() == static::STATUS_MULTIBYTE) {
return mb_strtolower($text);
}
else {
// Use C-locale for ASCII-only lowercase.
$text = strtolower($text);
// Case flip Latin-1 accented letters.
$text = preg_replace_callback('/\\xC3[\\x80-\\x96\\x98-\\x9E]/', '\\Drupal\\Component\\Utility\\Unicode::caseFlip', $text);
return $text;
}
}
/**
* Capitalizes the first character of a UTF-8 string.
*
* @param string $text
* The string to convert.
*
* @return string
* The string with the first character as uppercase.
*/
public static function ucfirst($text) {
return static::strtoupper(static::substr($text, 0, 1)) . static::substr($text, 1);
}
/**
* Converts the first character of a UTF-8 string to lowercase.
*
* @param string $text
* The string that will be converted.
*
* @return string
* The string with the first character as lowercase.
*
* @ingroup php_wrappers
*/
public static function lcfirst($text) {
// Note: no mbstring equivalent!
return static::strtolower(static::substr($text, 0, 1)) . static::substr($text, 1);
}
/**
* Capitalizes the first character of each word in a UTF-8 string.
*
* @param string $text
* The text that will be converted.
*
* @return string
* The input $text with each word capitalized.
*
* @ingroup php_wrappers
*/
public static function ucwords($text) {
$regex = '/(^|[' . static::PREG_CLASS_WORD_BOUNDARY . '])([^' . static::PREG_CLASS_WORD_BOUNDARY . '])/u';
return preg_replace_callback($regex, function (array $matches) {
return $matches[1] . Unicode::strtoupper($matches[2]);
}, $text);
}
/**
* Cuts off a piece of a string based on character indices and counts.
*
* Follows the same behavior as PHP's own substr() function. Note that for
* cutting off a string at a known character/substring location, the usage of
* PHP's normal strpos/substr is safe and much faster.
*
* @param string $text
* The input string.
* @param int $start
* The position at which to start reading.
* @param int $length
* The number of characters to read.
*
* @return string
* The shortened string.
*/
public static function substr($text, $start, $length = NULL) {
if (static::getStatus() == static::STATUS_MULTIBYTE) {
return $length === NULL ? mb_substr($text, $start) : mb_substr($text, $start, $length);
}
else {
$strlen = strlen($text);
// Find the starting byte offset.
$bytes = 0;
if ($start > 0) {
// Count all the characters except continuation bytes from the start
// until we have found $start characters or the end of the string.
$bytes = -1;
$chars = -1;
while ($bytes < $strlen - 1 && $chars < $start) {
$bytes++;
$c = ord($text[$bytes]);
if ($c < 0x80 || $c >= 0xc0) {
$chars++;
}
}
}
elseif ($start < 0) {
// Count all the characters except continuation bytes from the end
// until we have found abs($start) characters.
$start = abs($start);
$bytes = $strlen;
$chars = 0;
while ($bytes > 0 && $chars < $start) {
$bytes--;
$c = ord($text[$bytes]);
if ($c < 0x80 || $c >= 0xc0) {
$chars++;
}
}
}
$istart = $bytes;
// Find the ending byte offset.
if ($length === NULL) {
$iend = $strlen;
}
elseif ($length > 0) {
// Count all the characters except continuation bytes from the starting
// index until we have found $length characters or reached the end of
// the string, then backtrace one byte.
$iend = $istart - 1;
$chars = -1;
$last_real = FALSE;
while ($iend < $strlen - 1 && $chars < $length) {
$iend++;
$c = ord($text[$iend]);
$last_real = FALSE;
if ($c < 0x80 || $c >= 0xc0) {
$chars++;
$last_real = TRUE;
}
}
// Backtrace one byte if the last character we found was a real
// character and we don't need it.
if ($last_real && $chars >= $length) {
$iend--;
}
}
elseif ($length < 0) {
// Count all the characters except continuation bytes from the end
// until we have found abs($start) characters, then backtrace one byte.
$length = abs($length);
$iend = $strlen;
$chars = 0;
while ($iend > 0 && $chars < $length) {
$iend--;
$c = ord($text[$iend]);
if ($c < 0x80 || $c >= 0xc0) {
$chars++;
}
}
// Backtrace one byte if we are not at the beginning of the string.
if ($iend > 0) {
$iend--;
}
}
else {
// $length == 0, return an empty string.
return '';
}
return substr($text, $istart, max(0, $iend - $istart + 1));
}
}
/**
* Truncates a UTF-8-encoded string safely to a number of characters.
*
* @param string $string
* The string to truncate.
* @param int $max_length
* An upper limit on the returned string length, including trailing ellipsis
* if $add_ellipsis is TRUE.
* @param bool $wordsafe
* If TRUE, attempt to truncate on a word boundary. Word boundaries are
* spaces, punctuation, and Unicode characters used as word boundaries in
* non-Latin languages; see Unicode::PREG_CLASS_WORD_BOUNDARY for more
* information. If a word boundary cannot be found that would make the length
* of the returned string fall within length guidelines (see parameters
* $max_length and $min_wordsafe_length), word boundaries are ignored.
* @param bool $add_ellipsis
* If TRUE, add '...' to the end of the truncated string (defaults to
* FALSE). The string length will still fall within $max_length.
* @param int $min_wordsafe_length
* If $wordsafe is TRUE, the minimum acceptable length for truncation (before
* adding an ellipsis, if $add_ellipsis is TRUE). Has no effect if $wordsafe
* is FALSE. This can be used to prevent having a very short resulting string
* that will not be understandable. For instance, if you are truncating the
* string "See myverylongurlexample.com for more information" to a word-safe
* return length of 20, the only available word boundary within 20 characters
* is after the word "See", which wouldn't leave a very informative string. If
* you had set $min_wordsafe_length to 10, though, the function would realise
* that "See" alone is too short, and would then just truncate ignoring word
* boundaries, giving you "See myverylongurl..." (assuming you had set
* $add_ellipses to TRUE).
*
* @return string
* The truncated string.
*/
public static function truncate($string, $max_length, $wordsafe = FALSE, $add_ellipsis = FALSE, $min_wordsafe_length = 1) {
$ellipsis = '';
$max_length = max($max_length, 0);
$min_wordsafe_length = max($min_wordsafe_length, 0);
if (static::strlen($string) <= $max_length) {
// No truncation needed, so don't add ellipsis, just return.
return $string;
}
if ($add_ellipsis) {
// Truncate ellipsis in case $max_length is small.
$ellipsis = static::substr('…', 0, $max_length);
$max_length -= static::strlen($ellipsis);
$max_length = max($max_length, 0);
}
if ($max_length <= $min_wordsafe_length) {
// Do not attempt word-safe if lengths are bad.
$wordsafe = FALSE;
}
if ($wordsafe) {
$matches = array();
// Find the last word boundary, if there is one within $min_wordsafe_length
// to $max_length characters. preg_match() is always greedy, so it will
// find the longest string possible.
$found = preg_match('/^(.{' . $min_wordsafe_length . ',' . $max_length . '})[' . Unicode::PREG_CLASS_WORD_BOUNDARY . ']/u', $string, $matches);
if ($found) {
$string = $matches[1];
}
else {
$string = static::substr($string, 0, $max_length);
}
}
else {
$string = static::substr($string, 0, $max_length);
}
if ($add_ellipsis) {
// If we're adding an ellipsis, remove any trailing periods.
$string = rtrim($string, '.');
$string .= $ellipsis;
}
return $string;
}
/**
* Compares UTF-8-encoded strings in a binary safe case-insensitive manner.
*
* @param string $str1
* The first string.
* @param string $str2
* The second string.
*
* @return int
* Returns < 0 if $str1 is less than $str2; > 0 if $str1 is greater than
* $str2, and 0 if they are equal.
*/
public static function strcasecmp($str1, $str2) {
return strcmp(static::strtoupper($str1), static::strtoupper($str2));
}
/**
* Encodes MIME/HTTP headers that contain incorrectly encoded characters.
*
* For example, Unicode::mimeHeaderEncode('tést.txt') returns
* "=?UTF-8?B?dMOpc3QudHh0?=".
*
* See http://www.rfc-editor.org/rfc/rfc2047.txt for more information.
*
* Notes:
* - Only encode strings that contain non-ASCII characters.
* - We progressively cut-off a chunk with self::truncateBytes(). This ensures
* each chunk starts and ends on a character boundary.
* - Using \n as the chunk separator may cause problems on some systems and
* may have to be changed to \r\n or \r.
*
* @param string $string
* The header to encode.
*
* @return string
* The mime-encoded header.
*/
public static function mimeHeaderEncode($string) {
if (preg_match('/[^\\x20-\\x7E]/', $string)) {
$chunk_size = 47;
// floor((75 - strlen("=?UTF-8?B??=")) * 0.75);
$len = strlen($string);
$output = '';
while ($len > 0) {
$chunk = static::truncateBytes($string, $chunk_size);
$output .= ' =?UTF-8?B?' . base64_encode($chunk) . "?=\n";
$c = strlen($chunk);
$string = substr($string, $c);
$len -= $c;
}
return trim($output);
}
return $string;
}
/**
* Decodes MIME/HTTP encoded header values.
*
* @param string $header
* The header to decode.
*
* @return string
* The mime-decoded header.
*/
public static function mimeHeaderDecode($header) {
$callback = function ($matches) {
$data = $matches[2] == 'B' ? base64_decode($matches[3]) : str_replace('_', ' ', quoted_printable_decode($matches[3]));
if (strtolower($matches[1]) != 'utf-8') {
$data = static::convertToUtf8($data, $matches[1]);
}
return $data;
};
// First step: encoded chunks followed by other encoded chunks (need to collapse whitespace)
$header = preg_replace_callback('/=\\?([^?]+)\\?(Q|B)\\?([^?]+|\\?(?!=))\\?=\\s+(?==\\?)/', $callback, $header);
// Second step: remaining chunks (do not collapse whitespace)
return preg_replace_callback('/=\\?([^?]+)\\?(Q|B)\\?([^?]+|\\?(?!=))\\?=/', $callback, $header);
}
/**
* Flip U+C0-U+DE to U+E0-U+FD and back. Can be used as preg_replace callback.
*
* @param array $matches
* An array of matches by preg_replace_callback().
*
* @return string
* The flipped text.
*/
public static function caseFlip($matches) {
return $matches[0][0] . chr(ord($matches[0][1]) ^ 32);
}
/**
* Checks whether a string is valid UTF-8.
*
* All functions designed to filter input should use drupal_validate_utf8
* to ensure they operate on valid UTF-8 strings to prevent bypass of the
* filter.
*
* When text containing an invalid UTF-8 lead byte (0xC0 - 0xFF) is presented
* as UTF-8 to Internet Explorer 6, the program may misinterpret subsequent
* bytes. When these subsequent bytes are HTML control characters such as
* quotes or angle brackets, parts of the text that were deemed safe by filters
* end up in locations that are potentially unsafe; An onerror attribute that
* is outside of a tag, and thus deemed safe by a filter, can be interpreted
* by the browser as if it were inside the tag.
*
* The function does not return FALSE for strings containing character codes
* above U+10FFFF, even though these are prohibited by RFC 3629.
*
* @param string $text
* The text to check.
*
* @return bool
* TRUE if the text is valid UTF-8, FALSE if not.
*/
public static function validateUtf8($text) {
if (strlen($text) == 0) {
return TRUE;
}
// With the PCRE_UTF8 modifier 'u', preg_match() fails silently on strings
// containing invalid UTF-8 byte sequences. It does not reject character
// codes above U+10FFFF (represented by 4 or more octets), though.
return preg_match('/^./us', $text) == 1;
}
/**
* Finds the position of the first occurrence of a string in another string.
*
* @param string $haystack
* The string to search in.
* @param string $needle
* The string to find in $haystack.
* @param int $offset
* If specified, start the search at this number of characters from the
* beginning (default 0).
*
* @return int|false
* The position where $needle occurs in $haystack, always relative to the
* beginning (independent of $offset), or FALSE if not found. Note that
* a return value of 0 is not the same as FALSE.
*/
public static function strpos($haystack, $needle, $offset = 0) {
if (static::getStatus() == static::STATUS_MULTIBYTE) {
return mb_strpos($haystack, $needle, $offset);
}
else {
// Remove Unicode continuation characters, to be compatible with
// Unicode::strlen() and Unicode::substr().
$haystack = preg_replace("", '', $haystack);
$needle = preg_replace("", '', $needle);
return strpos($haystack, $needle, $offset);
}
}
}