Learning Redux

No side effects

A pure counter function would look like this:

function counter (i) {  return i + 1}

With the same input, it will always return the same output:

• counter(0): 1
• counter(0): 1

If we want to count, we will need to call the counter function multiple times or pass the result of a previous call to counter() to it:

• counter(counter(0)): 2
• counter(1): 2