Example
The combined assignment operators are a shortcut for an operation on some variable and subsequently assigning this new value to that variable.
Arithmetic:
$a = 1; // basic assignment
$a += 2; // read as '$a = $a + 2'; $a now is (1 + 2) => 3
$a -= 1; // $a now is (3 - 1) => 2
$a *= 2; // $a now is (2 * 2) => 4
$a /= 2; // $a now is (16 / 2) => 8
$a %= 5; // $a now is (8 % 5) => 3 (modulus or remainder)
// array +
$arrOne = array(1);
$arrTwo = array(2);
$arrOne += $arrTwo;
Processing Multiple Arrays Together
$a **= 2; // $a now is (4 ** 2) => 16 (4 raised to the power of 2)
Combined concatenation and assignment of a string:
$a = "a";
$a .= "b"; // $a => "ab"
Combined binary bitwise assignment operators:
$a = 0b00101010; // $a now is 42
$a &= 0b00001111; // $a now is (00101010 & 00001111) => 00001010 (bitwise and)
$a |= 0b00100010; // $a now is (00001010 | 00100010) => 00101010 (bitwise or)
$a ^= 0b10000010; // $a now is (00101010 ^ 10000010) => 10101000 (bitwise xor)
$a >>= 3; // $a now is (10101000 >> 3) => 00010101 (shift right by 3)
$a <<= 1; // $a now is (00010101 << 1) => 00101010 (shift left by 1)
