keys - php array_walk

Error de PHP ¿Por qué es "variable undefined" dentro de array_map?

Question

Estoy usando la función array_map en mi aplicación php. Definí la función array_map de esta manera.

$ratingID = $this->db->insert_id();
$rated_item_array = array_map(function ($a) {
return $a + array(''RatingID'' => $ratingID);
}, $rated_item_array);

Aviso de php viene

A PHP Error was encountered
Severity: Notice
Message: Undefined variable: ratingID

Cuando $ratingID el $ratingID . Imprime el valor correctamente, por lo que se define $ ratingID. ¿Por qué no está definido en la función array_map ? Mi $rated_item_array es

Array
(
[0] => Array
(
[RatingFactorPreferenceID] => 1,
[PreferenceID] => 45,
[RatedValue] => 1,
[CreatedOn] => 1326790338,
[CreatedBy] => 25
)
[1] => Array
(
[RatingFactorPreferenceID] => 2,
[PreferenceID] => 45,
[RatedValue] => 1,
[CreatedOn] => 1326790338,
[CreatedBy] => 25
)
[2] => Array
(
[RatingFactorPreferenceID] => 3,
[PreferenceID] => 45,
[RatedValue] => 1,
[CreatedOn] => 1326790338,
[CreatedBy] => 25
)
)

Answer 1

$rated_item_array = array_map(
function ($a) use ($ratingID){
return $a + array(''RatingID'' => $ratingID );
},
$rated_item_array
);