"init terminating in do_boot" is thrown when executing Erlang script

Question

Here's my code in 'factorial.erl':

-module(factorial).
-author("jasonzhu").

%% API
-export([fac/1]).

fac(0) -> 1;
fac(N) -> N * fac(N-1).

When interacting this code in prompt, it works fine:

1> c(factorial).
{ok,factorial}
2> factorial:fac(20).
2432902008176640000

But if I compile and execute it from command line, some errors occurred.

Jasons-MacBook-Pro:src jasonzhu$ erlc factorial.erl 
Jasons-MacBook-Pro:src jasonzhu$ erl -noshell -s factorial fac 20 -s init stop
{"init terminating in do_boot",{badarith,[{factorial,fac,1,[{file,"factorial.erl"},{line,8}]},{init,start_it,1,[]},{init,start_em,1,[]}]}}

Crash dump was written to: erl_crash.dump
init terminating in do_boot ()

Could anyone help me out? I'm a newbie on Erlang, many thanks!

Answer 1

-noshell syntax is

erl -noshell -s Module Function Arguments

where Arguments is a list of atoms. So you have to get 'fac' argument from list and convert it to integer.

This

-module(factorial).

-export([fac/1]).

fac([N]) ->
    X = fac(list_to_integer(atom_to_list(N))),
    io:format("~p~n", [X]);
fac(0) -> 1;
fac(N) -> N * fac(N-1).

works

>>> erl -noshell -s factorial fac 20 -s init stop
2432902008176640000