TypeScript - calculate crc32

const CRC_TABLE: number[] = Array(256);

​

for (let i = 0; i < 256; ++i) {

    let code = i;

    for (let j = 0; j < 8; ++j) {

        code = code & 0x01 ? 0xedb88320 ^ (code >>> 1) : code >>> 1;

    }

    CRC_TABLE[i] = code;

}

​

const crc32 = (text: string): number => {

    let crc = -1;

    for (let i = 0; i < text.length; ++i) {

        const code = text.charCodeAt(i);

        crc = CRC_TABLE[(code ^ crc) & 0xff] ^ (crc >>> 8);

    }

    return (-1 ^ crc) >>> 0;

};

​

​

// Usage example:

​

console.log(crc32('This is example text ...'));  // 3473739588

3473739588