15.22

Conditional And Operator

&&

EXPRESSIONS

For

^

, the result value is

true

 if the operand values are different; otherwise,

the result is

false

.

For

|

, the result value is

false

 if both operand values are

false

; otherwise,

the result is

true

.

15.22   Conditional And Operator

&&

The

&&

 operator is like

&

 ( 15.21.2), but evaluates its right hand operand only if

the value of its left hand operand is

true

. It is syntactically left associative (it

groups left to right). It is fully associative with respect to both side effects and

result value; that is, for any expressions

a

,

b

, and

c

, evaluation of the expression

((a)&&(b))&&(c)

 produces the same result, with the same side effects occur 

ring in the same order, as evaluation of the expression

(a)&&((b)&&(c))

.

ConditionalAndExpression:

InclusiveOrExpression

ConditionalAndExpression

 &&

InclusiveOrExpression

Each operand of

&&

 must be of type

boolean

, or a compile time error occurs.

The type of a conditional and expression is always

boolean

.

At run time, the left hand operand expression is evaluated first; if its value is

false

, the value of the conditional and expression is

false

 and the right hand

operand expression is not evaluated. If the value of the left hand operand is

true

,

then the right hand expression is evaluated and its value becomes the value of the

conditional and expression. Thus,

&&

 computes the same result as

&

 on

boolean

operands. It differs only in that the right hand operand expression is evaluated

conditionally rather than always.

15.23   Conditional Or Operator

||

The

||

 operator is like

|

 ( 15.21.2), but evaluates its right hand operand only if

the value of its left hand operand is

false

. It is syntactically left associative (it

groups left to right). It is fully associative with respect to both side effects and

result value; that is, for any expressions

a

,

b

, and

c

, evaluation of the expression

((a)||(b))||(c)

 produces the same result, with the same side effects occur 

ring in the same order, as evaluation of the expression

(a)||((b)||(c))

.

ConditionalOrExpression:

ConditionalAndExpression

ConditionalOrExpression

 ||

ConditionalAndExpression

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