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PHP return(value); vs return value;

开发者 https://www.devze.com 2023-01-01 01:40 出处:网络
Is there any difference between return($var)开发者_运维技巧; and return $var; other then wrapping it in parentheses? Unless you are returning by reference, they mean the same thing. It is preferable t

Is there any difference between return($var)开发者_运维技巧; and return $var; other then wrapping it in parentheses?


Unless you are returning by reference, they mean the same thing. It is preferable to exclude the parentheses. From the docs:

Note: Note that since return() is a language construct and not a function, the parentheses surrounding its arguments are not required. It is common to leave them out, and you actually should do so as PHP has less work to do in this case.

Note: You should never use parentheses around your return variable when returning by reference, as this will not work. You can only return variables by reference, not the result of a statement. If you use return ($a); then you're not returning a variable, but the result of the expression ($a) (which is, of course, the value of $a).


From the PHP Manual:

"You should never use parentheses around your return variable when returning by reference, as this will not work. You can only return variables by reference, not the result of a statement. If you use return ($a); then you're not returning a variable, but the result of the expression ($a) (which is, of course, the value of $a)."

Edit: This means that there is a difference between return($var) and return $var. Specifically, the former will return the value of $var and the latter will return $var itself.


Note that since return() is a language construct and not a function, the parentheses surrounding its arguments are not required. It is common to leave them out, and you actually should do so as PHP has less work to do in this case.

You should never use parentheses around your return variable when returning by reference, as this will not work. You can only return variables by reference, not the result of a statement. If you use return ($a); then you're not returning a variable, but the result of the expression ($a) (which is, of course, the value of $a).

(Source)


Yes. If you use parenthesis it will become an expression that PHP will have to solve first, which is a waste of a few CPU cycles. Additionally, you cannot return by reference using return($var);, only by using return $var;

This is all clearly stated in the manual.


It's a language construct, not a function, so both are working almost the same. There are two differences tho. Quoting php.net:

If no parameter is supplied, then the parentheses must be omitted and NULL will be returned. Calling return() with parentheses but with no arguments will result in a parse error.

and

You should never use parentheses around your return variable when returning by reference, as this will not work. You can only return variables by reference, not the result of a statement. If you use return ($a); then you're not returning a variable, but the result of the expression ($a) (which is, of course, the value of $a).

Source: php.net


The only time I use parenthesis is when returning two values with an array.

return array($val,$valb);

This example is different than your initial question, however this is the only instance where I think parenthesis are required.

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