Question

I’m struggling to understand why the following code is echoing out ‘FOO2’ when i’m expecting ‘FOO1’

$tmp = 'foo1';
echo $tmp == 'foo1' ? 'FOO1' : $tmp == 'foo2' ? 'FOO2' : 'NO FOO';

Answer 1

basically PHP breaks this down to:

$tmp = 'foo1';
echo ($tmp == 'foo1' ? 'FOO1' : $tmp == 'foo2') ? 'FOO2' : 'NO FOO';

the part in parentheses will return FOO1 which evaluates to TRUE so the second conditional statement essentially is TRUE ? 'FOO2' : 'NO FOO'; – which in turn always evaluates to 'FOO2'

Note: This is different from C ternary operator associativity