Erlang io:formatting a binary to hex

Question

Can I format an Erlang binary so that each byte is written in hex? I.e.,

> io:format(???, [<<255, 16>>]).
<>

Answer 1

if you prefer to make a binary string instead of erlang default list strings, you may use binary comprehension syntax, like what I did on my sha1 generating code:

1> << << if N >= 10 -> N -10 + $a;
1>          true    -> N     + $0 end >>
1>    || <<N:4>> <= crypto:hash(sha, "hello world") >>.
<<"2aae6c35c94fcfb415dbe95f408b9ce91ee846ed">>

same as in python binascii.b2a_hex:

>>> binascii.b2a_hex(sha.new('hello world').digest())
'2aae6c35c94fcfb415dbe95f408b9ce91ee846ed'