function binToDec(bin) {
let num = 0;
for (let i = 0; i < bin.length; i++) {
num = num << 1;
if (bin[i] === '1') ++num;
}
return num;
}This converts a string of a binary number to a decimal, unsigned integer.
binToDec('0010'); // 2
binToDec('10010'); // 18
binToDec('11111111'); // 255