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Comment by riffraff | Hacker News Reader

This often comes up, but I never understood why.

Is it a case of e.g.

    If "null" == null

With implicit conversion?

What language does this? I think perl might allow it by accident if you don't use strict/warnings pragmas, but it seems weird. Is it a PHPism perhaps?

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I have seen before that null is encoded as "null" when an encoding doesn't support null itself, e.g. multipart/form-data. Of course, then the server will treat any "null" as null

PHP understands this properly:

    var_dump( "null" == null );
    // bool(false)

> What language does this?

SQL injection, for one. For once, not PHP (thankfully).

But an SQL injection is an exploit. In SQL ‘Null‘ != Null

Right, but a ton of well-meaning but cure-is-worse-than-disease "Web Application Firewall" tools still block it

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