Ternary Operator - What am I doing wrong?

Question

$profilePic = isset( $userservice->getProfilePic($userid))      
              ?  filter($userservice->getProfilePic($userid)) 
              : '<img></img>';

Returns the error:

Fatal error: Can't use method return value in write context

What am I doing wrong here?

Can you please show us the declaration part of `filter()` and `var_dump` of `$userservice`? — Praveen Kumar Purushothaman, Jul 31 '12 at 07:26

Carlos Campderrós · Answer 1 · 2012-07-31T07:32:28.513

9

You can only use isset with variables, not with return values from functions, as isset is not a function, but a language construct.

addendum: There was a vote to allow passing arbitrary expression arguments to isset and empty, but finally isset was dropped from the final implementation.

edited Jul 31 '12 at 07:32

answered Jul 31 '12 at 07:27

Carlos Campderrós

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in other words, a function result **is** set, no matter what – Gabi Purcaru Jul 31 '12 at 07:27
Gotcha, thanks. So, if I want to check if it's empty or not would `!empty` do the trick? – Paul Dessert Jul 31 '12 at 07:30
1

@Paul see my addendum. Right now, using `empty` will fail the same, but you can set `$profilePic = $userservice->getProfilePic($userid);` and then `!empty($profilePic) ? ... : ... ;` – Carlos Campderrós Jul 31 '12 at 07:34
Thanks @CarlosCampderrós. I'm trying to clean up some code and get rid of a few 'if` statements. My approach doesn't really seem to help me much :) – Paul Dessert Jul 31 '12 at 07:35
1

@Paul You need neither `isset` nor `empty`. A simple `== false` or `!` suffices. – deceze Jul 31 '12 at 07:36
@deceze - Wow, I'm dense tonight! :) That's exactly what I'm trying to achieve and looked right past it. Thanks much! – Paul Dessert Jul 31 '12 at 07:41

deceze · Accepted Answer · 2012-07-31T07:39:17.917

3

isset only and exclusively works on variables. You do not need it for functions. Your ternary operator is fine.

See The Definitive Guide To PHP's isset And empty.

edited Jul 31 '12 at 07:39

answered Jul 31 '12 at 07:27

deceze

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score 0 · Answer 3 · answered Jul 31 '12 at 07:27

0

try: "

$tempPic=$userservice->getProfilePic($userid);
         $profilePic = isset($tempPic ) ?  filter($userservicegetProfilePic($userid))  : '<img></img>';

"

answered Jul 31 '12 at 07:27

ka_lin

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This make no sense. It is always isset. Did you mean empty()? – dlitsman Jul 31 '12 at 07:29
`empty` is just as superfluous, you don't need either. – deceze Jul 31 '12 at 07:35

Ternary Operator - What am I doing wrong?

3 Answers3