Dynamic Class Property Definition in PHP
Assigning property values dynamically within the same class is not possible in PHP due to limitations imposed by the language's compilation process. The error you encountered stems from attempting to reference an object property within its own definition, which is not allowed.
Constructor Approach
To address this issue, class properties that depend on other properties can be initialized within the constructor method. For instance, in your example:
public function __construct() {
$this->fullname = $this->firstname . ' ' . $this->lastname;
$this->totalBal = $this->balance + $this->newCredit;
}
This approach ensures that the dynamic properties are calculated and assigned after the object has been created and all its properties have been initialized.
Why Default Assignments are Static
According to the PHP manual, default assignments for class properties must be constant values that can be evaluated at compile time. This restriction prevents the use of run-time information or dynamic values within property definitions.
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