KDOT KDOT - 22 days ago 12
PHP Question

Cannot unpack array with string keys


FATAL ERROR Uncaught Error: Cannot unpack array with string keys


I know I can simply run the method
fetch()
twice and pass the
['q']
and
['bind']
but I am trying to get to grips with using the new
...
to unpack values. I want to pass the values like so:

(string) SQL, (Array) Bind Values


But I think it tries to unpack the bind values array as well as the response array from the
fetch()
method. Is it possible to unpack this array (looks something like this:)

array(2) {
["q"]=> string(7) "example"
["bind"]=> array(1) {
["example"]=> string(3) "one"
}
}


This is the whole code, in-case you need to see how it all fits together:

class ModelController {
public static function execute($sql, $vals) {
var_dump($vals);
}
}

class ModelContainer {

private $queries = [];

public function add_model(Model $model, $name) {
$this->queries[$name] = $model;
return $this;
}

public function exec_all() {
foreach($this->queries as $q) {
ModelController::execute(...$q->fetch());
}
}

public function exec($name) {

}

}

class Model {

private $sql;
private $vals = [];


public function set_q($statement) {
$this->sql = $statement;
return $this;
}

public function bind($vals = []) {
$this->vals = $vals;
return $this;
}

public function fetch() {
return ['q' => (string)$this->sql,
'bind' => $this->vals ];
}
}

$m = new ModelContainer();
$m->add_model((new Model)->set_q('example sql here')->bind(['example' => 'example value here']), 'one');
$m->exec_all();

Answer

The problem is that the "splat" operator (array unpacking operator or ...) does not work with associative arrays. Example:

$array = [ 1,2,3 ];
$assoc = [ "one" => 1, "two" => 2, "three" , 3 ];

var_dump(...$array); //Works
var_dump(...$assoc); //Doesn't work

You need to force an array to be numerically indexed in order to unpack it. You do this using array_values:

$values = array_values($q->fetch());
ModelController::execute(...$values);

Array values will ensure all values have a sequential numeric key.