Learning Functional Programming in Go

What is tail recursion?

Recursion is where a function calls itself. Tail recursion is where a recursive call is the last line of our function. For example, the last line of our fib function calls itself twice:

func fib(x int) int {    if x == 0 {        return 0    } else if x <= 2 {        return 1    } else {        return fib(x-2) + fib(x-1)    }}

In this case, there is no reason to preserve the state. There are no other lines of code left to execute in the function and we don’t care about any values of any variables that may have been assigned prior to reaching our return statement.

If our return statement occurred in the middle of our function, the Go runtime would need to remember our function’s address in order to return to it, and it would need to store function-local ...