Initialization Loop

Why This Happens

Go initializes package-level variables in dependency order. If variable A's initializer references B and B's initializer references A, Go cannot determine the initialization order and reports an error. Break the cycle by computing one value in an init() function.

The Problem

var a = b + 1
var b = a + 1 // initialization loop

The Fix

var a int
var b int

func init() {
    a = 1
    b = a + 1
}

Step-by-Step Fix

1. 1

   Identify the loop

   Read the error to see which variables form the initialization cycle.

2. 2

   Break the dependency

   Determine which variable should be initialized first.

3. 3

   Use init() function

   Move one or both initializations into an init() function where you control the order.