Specifications

PHP supports logical AND, OR, XOR (exclusive or), and NOT.

The set of logical operators and their use is summarized in Table 1.4.

TABLE 1.4 PHP’s Logical Operators

Operator Name Use Result

! NOT !$b Returns true if $b is false, and vice versa

&& AND $a && $b Returns true if both $a and $b are true; other-

wise false

|| OR $a || $b Returns true if either $a or $b or both are true;

otherwise false

and AND $a and $b Same as &&, but with lower precedence

or OR $a or $b Same as ||, but with lower precedence

The and and or operators have lower precedence than the && and || operators. We will cover

precedence in more detail later in this chapter.

Bitwise Operators

The bitwise operators enable you to treat an integer as the series of bits used to represent it.

You probably will not find a lot of use for these in PHP, but a summary of bitwise operators is

shown in Table 1.5.

TABLE 1.5 PHP’s Bitwise Operators

Operator Name Use Result

& bitwise AND $a & $b Bits set in $a and $b are set in the result

| bitwise OR $a | $b Bits set in $a or $b are set in the result

~ bitwise NOT ~$a Bits set in $a are not set in the result,

and vice versa

^ bitwise XOR $a ^ $b Bits set in $a or $b but not in both are

set in the result

<< left shift $a << $b Shifts $a left $b bits

>> right shift $a >> $b Shifts $a right $b bits

PHP Crash Course

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