任何人都可以解释为什么NAN和一个变量等于NAN根据 PHP 的版本而表现不同?
考虑以下代码:
$nan = NAN;
print "PHP Version: " . phpversion(). "\n" .
'0 < NAN ? ' . ( 0 < NAN ? 'TRUE' : 'FALSE' ) . "\n" .
'0 > NAN ? ' . ( 0 > NAN ? 'TRUE' : 'FALSE' ) . "\n" .
'0 == NAN ? ' . ( 0 == NAN ? 'TRUE' : 'FALSE' ) . "\n" .
'0 < $nan ? ' . ( …Run Code Online (Sandbox Code Playgroud)