if ($x)
   $y = 5;
else
   $y = 7;

$z = $y;  <==== Netbeans warns that $y many not be defined.

FILE: foo.php

--------------------------------------------------------------------------------
FOUND 6 ERROR(S) AND 1 WARNING(S) AFFECTING 7 LINE(S)
--------------------------------------------------------------------------------
  1 | ERROR   | End of line character is invalid; expected "n" but found
    |         | "rn"
  2 | ERROR   | Missing file doc comment
 41 | ERROR   | Space found before comma in function call
 42 | ERROR   | Multi-line function call not indented correctly; expected 20
    |         | spaces but found 22
 70 | ERROR   | Opening parenthesis of a multi-line function call must be the
    |         | last content on the line
 74 | ERROR   | Closing parenthesis of a multi-line function call must be on a
    |         | line by itself
 84 | WARNING | Line exceeds 85 characters; contains 102 characters
--------------------------------------------------------------------------------

php -l [file]