'&&' and 'AND' is different in PHP

 

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  • 'AND' vs '&&' as operator 10 answers

    • AND has lower precedence.

    $C = $A AND $B will be parsed as ($C = $A) AND $B .

    For variables $a and $b set as follows: 

    <?php

$a = 7;
$b = 0;

    the advantage of using AND is short-circuit evaluation that occurs in code like the following: 

    $c = $a AND $b;
var_dump( $c ); // 7

    Since the assignment operator has higher precedence than AND, the value of $a gets assigned to $c; $b gets skipped over.

    Consider the following code in contrast: 

    <?php

$c = $a && $b;
var_dump( $c ); // (bool) false

    In this snippet, && has a higher precedence than the assignment operator, and given the value of $a being non-zero, there is no short-circuiting. The result of this logical AND is based on the evaluation of both $a and $b. $a evaluates as true and $b as false. The overall value of the expression, false, is what gets assigned to $c. This result is quite different than in the prior example.

    both have same thing, but && has higher precedence than AND.

    for more:- 'AND' vs '&&' as operator

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