Question

I’m trying to convert an existing C function to Erlang but am having a bit of trouble understanding how it’s going to work. Let’s say I have the following function in C:

    void(int *x,int *y,int z,int a)
    {
     if(z<a)
      {
     *x = z + a;
     *y = z - a;
      }
     }

How would I write something like that in Erlang as a function module? I understand that normally you write your function and it would return an operation. But what if I have to do calculations on multiple variables?

Answer 1

you may return a tuple like: {X, Y}

Here is a function that doubles two values given as input:

-module(my_module).
-export([doubleus/2]).

doubleus(X, Y) ->
    {X*2, Y*2}.

In the shell:

1> c(my_module).
{ok, my_module}
2> {A, B} = my_module:doubleus(3,4).
{6, 8}