On: These are things in PHP which make me sad

[paisawalla]

> It doesn't make sense unless you understand how PHP works ...

In other words: equality is not intuitive. Awesome!

---

Let's take a look at "how PHP works":

  0 == 08 // true!

WTF, really? Well, let's just use the magical 'I-mean-actual-equality-not-some-other-kind-of-equality' operator:

  0 === 08 // also true!

  (Sonofabitch/Facepalm) * Infinity

Of all the areas of a language in which one could gain expertise in, I think testing equality should not be one of the more difficult to master.

This is just stupid behavior. 08 is an invalid octal sequence, but no error is raised. You can't detect this condition unless you do your own pre-parsing before allowing PHP to try to parse it!

[bnr → paisawalla]

That's the grammar for PHP integer literals[1]:

    decimal     : [1-9][0-9]*
                | 0
    
    hexadecimal : 0[xX][0-9a-fA-F]+
    
    octal       : 0[0-7]+
    
    integer     : [+-]?decimal
                | [+-]?hexadecimal
                | [+-]?octal

"08" and "09" do not match any of these.

    php -r "var_dump(08);"

Yields "int(0)", while the case should rather be treated as a syntax error, if you ask me.

The bottom line probably is that your literals just shouldn't have leading zeroes…

[1] http://www.php.net/manual/en/language.types.integer.php

[wvenable → paisawalla]

I've been programming in PHP for a long time and I've never ever accidentally used an octal anywhere. Does such a non-problem really need this much attention?

[paisawalla → wvenable]

Perhaps you ask a user to enter the month of their CC expiration date, which is shown as 08/14 on their card.

  $v = validated_integer($user_input); // the user input 08
  if($v == 0 || $v === 0) { // let's just be safe
    
    // the Wrong Thing happens
    
  }

This is a contrived example, sure. But you've never checked to see if a user input the number 0? Or a non-zero, positive integer?

[wvenable → paisawalla]

I'm not sure what you expect to happen there but the following code always produces "Correct!":

    $user_input = '08';
    $user_input = (integer)$user_input;
    if ($user_input == 8) echo 'Correct!';
    if ($user_input == 0) echo 'Incorrect!';

If you take out the cast, the result is the same. If you change the numbers to '010' and 10 respectively, the result is also "Correct!". There is no weirdness.