title: Why doesn't ctype_alpha recognize integers -128 to 255 as letters if they are part of an array?
body: <p>Why do these return true:</p>
  
  <p><code>ctype_alpha(74); // returns true
  $bar = 74;
  ctype_alpha($bar); // returns true</code></p>
  
  <p>but this returns false:</p>
  
  <p><code>$foo = [1,2,3,'74'];
  ctype_alpha($foo[3]); // returns false</code></p>