What is the difference between the | and || operators?

Question

| and || - what is the difference between these two operators in PHP?

Answer 1

Meaning

| is binary operator, it will binary OR the bits of both the lefthand and righthand values.

|| is a boolean operator, it will short circuit when it encounters 'true' (any non-zero value, this includes non-empty arrays).

Examples

print_r(1 | 2)  // 3
print_r(1 || 2) // 1

When used with functions:

function numberOf($val) {
    echo "$val, ";
    return $val;
}

echo numberOf(1) | numberOf(2);  // Will print 1, 2, 3
echo numberOf(1) || numberOf(2); // Will print 1, 1