Provides some idiomatic tools to help when programming using Erlang's Binary primitive type.

my_binary.erl

-module(my_binary).
-export([foreach/3]).
-export([fold/4]).

break(Blocksize, Bin) ->
    <<Head:Blocksize/bits, Rest/bits>> = Bin,
    {Head, Rest}.

foreach(_, _, <<>>) -> ok;
foreach(F, Blocksize, Bin) ->
    {Head, Rest} = break(Blocksize, Bin),
    F(Head),
    foreach(F, Blocksize, Rest).

fold(_, Result, _, <<>>) -> Result;
fold(F, Initial, Blocksize, Bin) ->
    {Head, Rest} = break(Blocksize, Bin),
    Temp = F(Initial, Head),
    fold(F, Temp, Blocksize, Rest).