Ternary Operator not working in godaddy php (parsererror) [closed]

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<br />↵<b>Parse error</b>: syntax error, unexpected ':' in <b>.../ajax.php</b> on line <b>87</b>

LINE 87: $conditions = ($this->input->post()) ? : array('tutor'=>$this->session->userdata('user_id'));

line 87 works fine on localhost, but when I use godaddy I get that error. Is there something I need to set in php.ini or something to get Ternary operators to work?

Thanks!

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The ternary operator (as the name suggests) usually expects 3 arguments

$var = $expr ? $trueValue : $falseValue;

With PHP5.3 its allowed to omit $trueValue. In this case its $expr is used for it

$var = $expr ? : $falseValue;
// same as
$var = $expr ? $expr : $falseValue;

You probably don't have PHP5.3 on your server. As you can see in my example its quite easy to fix this and make it ready for pre-5.3

$conditions = ($this->input->post()) 
            ? ($this->input->post()) 
            : array('tutor'=>$this->session->userdata('user_id'));

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The syntax ? : you are using is PHP 5.3 only.

Set a default value:

$conditions = ($this->input->post()) ? $this->input->post() : array('tutor'=>$this->session->userdata('user_id'));

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The accepted answer is correct, but misses one important point:

$x = $a ? : $b; // valid in PHP 5.3

should indeed be replaced with

$x = $a ? $a : $b; // valid in older versions of PHP

However, when you're dealing with functions, not variables, be aware of side-effects:

$conditions = ($this->input->post()) 
        ? ($this->input->post()) 
        : array('tutor'=>$this->session->userdata('user_id'));

In the above case, if $this->input->post()returns a truthy value, the function will be executed again, which may not be what you want. You can see this more clearly by expanding the ternary operator to its full form:

if ($this->input->post()) {
    $conditions = $this->input->post();
} else {
    $conditions = array('tutor' => $this->session->userdata('user_id'));
}

You can see that the function is executed on lines one and two above. If you don't want that, try this instead:

if (!$conditions = $this->input->post()) {
    // Single equal sign in an if condition: make assignment, and check
    // whether the result is truthy.
    $conditions = array('tutor' => $this->session->userdata('user_id'));
}

This is a fairly common pattern in my own code. This will execute the function $this->input->post() only once. If the result is truthy, that result is stored in $conditions. If the result is not truthy, the code inside the if condition is run. This assigns the fallback value to $conditions. The benefit is that, in either case, $this->input->post() is run only once.