using dynamically named array inside foreach loop

[niche]

This works:

$names = 
array(
	array("name"=>"tom","gender"=>"m"),
	array("name"=>"jane","gender"=>"f"),
	array("name"=>"steve","gender"=>"m"),
	array("name"=>"mary","gender"=>"f"),
	array("name"=>"renae","gender"=>"f")
);	

$num = 30;
$wkvar = 'wk' . $num;

foreach ($names AS $val) {
	
	$wk30[] = $val;
	
	//$$wkvar[] =  $val;
	
}

var_dump($wk30);

this doesn’t and gives me this error, “Fatal error: Cannot use [] for reading”, (goggle hasn’t helped me):

$names = 
array(
	array("name"=>"tom","gender"=>"m"),
	array("name"=>"jane","gender"=>"f"),
	array("name"=>"steve","gender"=>"m"),
	array("name"=>"mary","gender"=>"f"),
	array("name"=>"renae","gender"=>"f")
);	

$num = 30;
$wkvar = 'wk' . $num;

foreach ($names AS $val) {
	
	//$wk30[] = $val;
	
	$$wkvar[] =  $val;
	
}

var_dump($wk30);

I need to use the 2nd (variable variable) approach. What am I doing wrong?

I tried adding a dynamic index unsuccessfully.

Edited August 31, 2018 by niche

[niche]

found the notation:

${$wkvar}[$i] =  $val;

If this has a name, pls let me know so I can get a ref?

 

stumbled on to by finally googling: "dynamic naming arrays  php"

 

[niche]

http://php.net/manual/en/language.variables.variable.php (3rd example).

 

[dsonesuk]

Define it as array before the foreach, then use array_push($$wkvar, $val);