What is a shorthand way for checking that multiple variables are ALL equal to the same value in an IF statement? (PHP)

Question

Is there a shorthand way of writing the code below?

if (($tstat=='no_prices')&&($l1stat=='no_prices')&&($l2stat=='no_prices')&&($l3stat=='no_prices'))
{                                   
    //do something
}

I tried using the below code,but it did something when one of the variables was not equal to 'no_prices'.

if (($tstat && $l1stat && $l2stat && $l3stat)=='no_prices')
{
    //do something
}

To check that the strings weren't causing problems I tried substituting 0 for 'no_prices' and 1 for other values, but the result was the same.

Answer 1

array_flip is several times faster than array_unique:

function all_equal($arr, $value) {
  return array_keys(array_flip($arr)) == array($value);
}

$arr = array($tstat, $l1stat, $l2stat, $l3stat);

echo all_equal($arr, 'no_prices');

A quick profile for the answers given thus far, for 1000 iterations on array length 1000:

  array_flip: 0.07321620 seconds
array_unique: 0.32569408 seconds
     foreach: 0.15136194 seconds
array_filter: 0.41404295 seconds

The code used to profile is here: http://codepad.org/szgNfWHe

Note: As @cypherabe rightly points out, array_flip does not overtake array_unique until the array has at least 5 elements, and does not overtake foreach until the array has at least 10 elements.

Answer 2

Unless I'm mistaken, there's no native way of doing this. If this is something that you have to check for often, try using a custom function for it, e.g.:

function allEquals($chkstr, $vals) {
    if (!is_array($vals)) { die('allEquals() $vals not an array'); }
    foreach ($vals AS $v) {
        if ($chkstr != $v) { return false; }
    }
    return true;
}