Question

Why it won’t work? Appears Parse error: syntax error, unexpected ‘:’ … on line 7

$a = 0; $b = 1; $c = 3; $d = 4;
if ($a == $b):
   if ($b == $c) {
       // something
   }
else:
   $c = $a;
endif;

But if i change it to (just added else statement):

$a = 0; $b = 1; $c = 3; $d = 4;
if ($a == $b):
   if ($b == $c) {
       // something
   } else {
       // something
   }
else:
   $c = $a;
endif;

It works fine.

Why is that? isn’t it a PHP bug? Or there is a rule about if…else i should know?

Anyway, i’m using PHP 5.3.3 version.

Answer 1

I am not sure if I would call this is a bug, but I believe you’re having this issue because of a dangling else, in conjunction with your mixed if-else syntax:

if ($a == $b):            // 1
    if ($b == $c) {       // 2 
        // something      // 3
    }                     // 4
else:                     // 5 - this else
    $c = $a;              // 6
endif;                    // 7

Note how the else on line 5 is ambiguous: it could “belong” either to the first or second if statements.

You can easily remove that ambiguity and fix your syntax error by adding a semicolon after your nested if:

if ($a == $b):            // 1
    if ($b == $c) {       // 2 
        // something      // 3
    };                    // 4 - here
else:                     // 5 
    $c = $a;              // 6
endif;                    // 7

On another note, please don’t use this syntax unless you want your fellow programmers to bludgeon you to death in your sleep.