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Date: Tue, 09 Jun 2015 13:38:44 +0100
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Subject: Re: [PHP-DEV] Array dereferencing of scalars
From: rowan.collins@gmail.com (Rowan Collins)

Christoph Becker wrote on 08/06/2015 22:11:
> The behavior of dereferencing scalars as if they were arrays or strings
> is arguable:
>
>    <?php
>    $foo = 42;
>    $foo['bar']; // => NULL

A few things to note here:

- accessing a *numeric* offset of a *string* is valid (selects a single 
character)
- accessing a *string* offset of another string is interpreted as access 
to character 0, with a Warning issued
- de-referencing this to two levels ($string['key']['key']) and then 
attempting to write is a Fatal error
- as discussed elsewhere, coercing a NULL to an array seems perfectly 
reasonable
- assigning to an offset of anything other than a string or array 
results in a Warning and no change to the variable

While I agree that it's kind of surprising not to get even a Notice in 
your example, I'm not 100% sure what the behaviour should be, given how 
many different scenarios already have different behaviour. Maybe someone 
needs to come up with a generalised rule?

Regards,
-- 
Rowan Collins
[IMSoP]