Illegal string offset - I'm feeling dumb today

Okay - so, I'm trying to rewrite some stuff, and happen upon an error that I don't really understand why is showing - I'm doing something wrong, of course, but today I don't think my brain is working as it should.

Okay, this is a var_dump of $_POST:

array(5) {
["userid"]=>
string(1) "1"
["nkid"]=>
array(2) {
[1]=>
string(1) "1"
["new"]=>
string(3) "new"
}
["nk_name"]=>
array(2) {
[1]=>
string(9) "Testadmin"
["new"]=>
string(19) "Admin Senior Senior"
}
["nk_phone"]=>
array(2) {
[1]=>
string(7) "1234567"
["new"]=>
string(8) "12345678"
}
["nk_email"]=>
array(2) {
[1]=>
string(13) "test@cntrl.no"
["new"]=>
string(18) "admins@example.com"
}
}

Code (markup):

Each of the $_POST-arrays are turned into their own, separate arrays (by some handler-function), and this is a dump of $nk_name:

array(2) {
[1]=>
string(9) "Testadmin"
["new"]=>
string(19) "Admin Senior Senior"
}

Code (markup):

All is well so far.
However, if I do this:

foreach ($nkid as $key => $value) {
  $nkid = $key;
  $nk_name = $nk_name[$key];
}

Code (markup):

I get an "Illegal string offset - 'new'"-error on the line with $nk_name - and I can't seem to figure out _why_ - the $nk_name is an array, and it contains a 'new' key, so why doesn't it work?

 

And... wow. Yup, I do feel dumb. Assigning something to an existing array... yeah. Noticed it right after I posted, was sure I already tested that, but... nope, I didn't. So, for those who don't follow: The solution is to not use the same variable name as the damn array you're trying to pull data from. *HEADDESK*

 

The $nkid was basically just
array (2) {
1 => 1
"new" => "new"
}

But, as you can see, I found the solution. Now I want to kill myself.