PHP Logical Operators: When Does \"&&\" Differ from \"and\"?

PHP Operator Equivalents: && vs. "and", || vs. "or"

In PHP, the logical operators && and || resemble their English counterparts, "and" and "or," respectively. Although their functionality often appears similar, there are subtle differences in their precedence levels.

Precedence

Unlike "and" and "or," which have a lower precedence relative to the assignment operator (=), && and || boast a higher precedence. This implies that (&&) and (|) will be evaluated before any assignment operations.

Practical Implications

While the precedence distinction usually remains inconsequential, certain scenarios can lead to unexpected results. For instance, consider the following code:

<code class="php">if ($a && $b = 1) {
    // ...
}</code>

If the intention is to check if both $a and $b are true, this code will fail because the assignment operator ($) takes precedence over the logical operator (&&). The code will instead assign the value 1 to $b and skip the conditional statement.

Other Operators with Word Equivalents

Other PHP operators also have associated English counterparts, such as:

• == - equal
• != - not equal
• < - less than
• > - greater than
• <= - less than or equal to
• >= - greater than or equal to

These word equivalents can occasionally enhance code readability, making it easier for non-programmers to understand the logic. However, their use is largely a matter of personal preference and style.

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