What does it mean to continue using the "equals sign"?

What does it mean to use "equal sign" consecutively?
Here is the code in a dedecms:

$dsql = $db =new dedesql (FALSE)

A "=" number is an assignment,

What does it mean to be represented in this ligatures way?

------Solution--------------------
Assigning values at the same time
$a = $b = 1;
Equivalent to
$a = 1;
$b = 1;

But it's important to note that
$dsql = $db =new dedesql (FALSE)
is not equivalent to
$dsql = new Dedesql (FALSE);
$db = new Dedesql (FALSE);

The former is a two variable is the same instance
The latter is an instance of two variables each
------Solution--------------------
And learned a little, the moderator is very bad
------Solution--------------------
It's never been used like that.
------Solution--------------------
This kind of thing needs not memory, but practice.

Class T {
  public $v = 1;
}

$a = $b = new T;
echo $a->v, ", $b->v; 1 1

$b->v = ' a ';
echo $a->v, ", $b->v;//a A

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