Question

I have a class like this:

// file /models/person.php
class Person 
{
    public function create_path()
    {
         self::log();
         path_helper($this);  //a global function in other php file
    }

    public function log()
    {
         echo "trying to create a path";
    }

}

This is the way how Person is instanciated:

//file /tools/Builder.php
include('/models/Person.php');
class Builder
{
    public function build()
    {
        $type = 'Person';
        $temp = new $type();
        $temp->create_path();
    } 
}

As you note in Person class, I am calling the object in question with $this reference. But this is not correct because an error is showed:

Message: Undefined variable: this

I suppose that $this reference point to other object or it is unable to work because the object is created from another script. Also, I tried to use self because there was not problem calling methods with that, but as parameter I get:

Message: Use of undefined constant self – assumed ‘self’

So, can you guide me to the right direction?

Answer 1

I tested your code out for myself, with a few minor changes. It appears to work properly.

• Changed self::log() to $this->log()
• Added global function path_helper (I have no idea what this does)

PHP

function path_helper(Person $object)
{
    var_dump($object);
}
class Person 
{
    public function create_path()
    {
         $this->log();
         path_helper($this);  //a global function in other php file
    }

    public function log()
    {
         echo "trying to create a path";
    }

}
class Builder
{
    public function build()
    {
        $type = 'Person';
        $temp = new $type();
        $temp->create_path();
    } 
}

$Build = new Builder();
$Build->build();

Result

trying to create a path

object(Person)[2]

Your code is correct and your going in the right direction.