Reference Error

What This Error Means

This error occurs when a variable is used before it is declared or assigned a value.

Why It Happens

In PHP, variables must be declared or initialized before they can be used. If a variable is not declared and is used, the PHP interpreter will throw a ReferenceError.

How to Fix It

1. 1To fix this error, you need to declare the variable before using it. You can do this by assigning a value to the variable or declaring it explicitly using the dollar sign ($). For example:
2. 2// Before (broken code)
3. 3$price = $product->price;
4. 4// After (fixed code)
5. 5$product = get_product();
6. 6$price = $product->price;

Example Code Solution

$product_price = $product->price;

$product = get_product();
$product_price = $product->price;