ctype_upper - PHP code example

The PHP Function Ctype_Uper() Checks If a String Starts With an Uppercase Letter

PHP is a powerful programming language that supports a wide range of character types, known as Ctypes. Every element of data read or written by a PHP application is represented as a string, which can range from human-readable sections of text (like To be or not to be) to sequences of raw bytes encoded as integers (like 123#Axy).

In general, a Ctype function checks whether or not a given string contains the characters that belong to its specific character class. The ctype_upper() function is a special case that checks if a string starts with an uppercase letter.

The ctype extension provides a variety of such functions that check for various types of characters. Some of them are based on character classes, while others are based on character values, such as decimal points, commas, and punctuation. The ctype_digit() function, for instance, is able to check whether or not a string contains valid hexadecimal digits (0-9).

Some of the ctype functions also check for visually printable characters. These include control characters and space. The ctype_graph() and ctype_print() functions are good examples of these.

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ctype_upper example

if (!function_exists('ctype_print')) {
    function ctype_print($text) { return p\Ctype::ctype_print($text); }
}
if (!function_exists('ctype_punct')) {
    function ctype_punct($text) { return p\Ctype::ctype_punct($text); }
}
if (!function_exists('ctype_space')) {
    function ctype_space($text) { return p\Ctype::ctype_space($text); }
}
if (!function_exists('ctype_upper')) {
    function ctype_upper($text) { return p\Ctype::ctype_upper($text); }
}
if (!function_exists('ctype_xdigit')) {
    function ctype_xdigit($text) { return p\Ctype::ctype_xdigit($text); }
}

->addViolation();
        }
    }

    private static function toBigInt(string $string): string
    {
        $chars = str_split($string);
        $bigInt = '';

        foreach ($chars as $char) {
            // Convert uppercase characters to ordinals, starting with 10 for "A"             if (ctype_upper($char)) {
                $bigInt .= (\ord($char) - 55);

                continue;
            }

            // Simply append digits             $bigInt .= $char;
        }

        return $bigInt;
    }

protected function execute(InputInterface $input, OutputInterface $output): int
    {
        $io = new SymfonyStyle($input, $output);
        $themeName = $input->getArgument('theme-name');

        if (!$themeName) {
            $question = new Question('Please enter a theme name: ');
            $themeName = $this->getHelper('question')->ask($input, $output, $question);
        }

        if (!ctype_upper((string) $themeName[0])) {
            $io->error('The name must start with an uppercase character');

            return self::FAILURE;
        }

        if (preg_match('/^[A-Za-z]\w{3,}$/', (string) $themeName) !== 1) {
            $io->error('Theme name is too short (min 4 characters), contains invalid characters');

            return self::FAILURE;
        }

// suffix may not succeed a consonant but next char is one                             break;
                        }
                    }

                    $newBase = substr($plural, 0, $pluralLength - $suffixLength);
                    $newSuffix = $map[4];

                    // Check whether the first character in the plural suffix                     // is uppercased. If yes, uppercase the first character in                     // the singular suffix too                     $firstUpper = ctype_upper($pluralRev[$j - 1]);

                    if (\is_array($newSuffix)) {
                        $singulars = [];

                        foreach ($newSuffix as $newSuffixEntry) {
                            $singulars[] = $newBase.($firstUpper ? ucfirst($newSuffixEntry) : $newSuffixEntry);
                        }

                        return $singulars;
                    }

$str = clone $this;
        $str->string .= 1 >= \count($suffix) ? ($suffix[0] ?? '') : implode('', $suffix);

        return $str;
    }

    public function camel(): static
    {
        $str = clone $this;

        $parts = explode(' ', trim(ucwords(preg_replace('/[^a-zA-Z0-9\x7f-\xff]++/', ' ', $this->string))));
        $parts[0] = 1 !== \strlen($parts[0]) && ctype_upper($parts[0]) ? $parts[0] : lcfirst($parts[0]);
        $str->string = implode('', $parts);

        return $str;
    }

    public function chunk(int $length = 1): array
    {
        if (1 > $length) {
            throw new InvalidArgumentException('The chunk length must be greater than zero.');
        }

if (!function_exists('ctype_print')) {
    function ctype_print(mixed $text): bool { return p\Ctype::ctype_print($text); }
}
if (!function_exists('ctype_punct')) {
    function ctype_punct(mixed $text): bool { return p\Ctype::ctype_punct($text); }
}
if (!function_exists('ctype_space')) {
    function ctype_space(mixed $text): bool { return p\Ctype::ctype_space($text); }
}
if (!function_exists('ctype_upper')) {
    function ctype_upper(mixed $text): bool { return p\Ctype::ctype_upper($text); }
}
if (!function_exists('ctype_xdigit')) {
    function ctype_xdigit(mixed $text): bool { return p\Ctype::ctype_xdigit($text); }
}