Question regarding Object Oriented PHP with the syntax involved.

Hello James Jones,

I like to think of the -> as a chain/ a link going left to right.

So you understand $this, which refers to the object itself.

In the example below, when we call $this->property_name, we are saying go to $this, and then from $this access what we have stored in the "property_name" of $this. If you have experience with arrays, think of it as key -> value storage. So we read property_name of $this and set to my_property_value.

<?php
$my_property_value = $this->property_name

Since it is a chain/ link you can navigate further than one level as long as each value in chain is an object.

So for your example, reading left to right, we know what $this is. But then we call $this->current(). This half of the statement is saying call the "current" method on the object of $this, ie current object, and read the function's returned value. Which in your example the function current of $this return an object. Since it is an object we a chain to read it's properties, which in example is to read the details property.

Below example is the same out as your example, but without chaining and more broken into steps.

<?php
class Example {
public function shortDescription()
    {
        // Execute current method and gets it's returned object and set to $current
        $current = $this->current();
        // From the $current object, read its property of "details" and set to $details
        $details = $current->details;

        if(strlen($details) < 510){
            $details = strip_tags($details);
        }
        return $details;
    }
}

So we are not passing the property to the method. In order to pass a value to a method/ function, requires you to put it between the ().

This example below would be passing a property to a method.See how in $this->trimString($this->details); we are taking $this->details value and passing it to $this->trimString() method.

<?php
class Example {
private $details = '<p>Example details</p>';

public function getShortDescription()
    {
        return $this->trimString($this->details);
    }
protected function trimString($string)
    {
        if(strlen($string) < 510){
            $string = strip_tags($string);
        }
        return $string;
    }
}