Model's function returns Undefined variable: role

Question

I have this table structure

users

• id
• email
• roles

role

• id
• role

role_user

• id
• role_id
• user_id

And I added a function in the User model which will check for Authenticated user's role. But I get it returns this error:

Undefined variable: role

//User.php
public function hasRole($role = null)
{
    $hasRole = false;
    $hasRole = !$this->roles->filter(function($item) {
        return $item->role == $role;
    })->isEmpty();
    return $hasRole;
}

So I can use into something like this - maybe inside a filter

if(Auth::user()->hasRole('encoder')) {
    //...
}

Answer 1

In PHP, By default, a function has no access to the variables declared outside of the function.

This variable can not be accessed from that closure

public function hasRole($role = null)
{
    $hasRole = false;
    $hasRole = !$this->roles->filter(function($item) {
        return $item->role == $role;
    })->isEmpty();            ^^^^^
    return $hasRole;
}

You can use the use keyword, which passes one variable to a function:

public function hasRole($role = null)
{
    $hasRole = false;
    $hasRole = !$this->roles->filter(function($item) use($role) {
        return $item->role == $role;
    })->isEmpty();
    return $hasRole;
}

They is more info about this particular problem on this blog post