Sha256: 83887aaa6ba006d58fc34c0faf8a039ac75dff024af2d356d2522af14972a36c
Contents?: true
Size: 1020 Bytes
Versions: 136
Compression:
Stored size: 1020 Bytes
Contents
-module(example).
-export([valid/1, test_version/0]).
checksum(Number) ->
checksum(
lists:reverse(
filter_input(Number)
),
odd,
0
).
is_numeric(Number) ->
lists:all(
fun(C) ->
(($0 =< C) andalso (C =< $9)) or (C == $\s)
end,
Number
).
filter_input(Number) ->
lists:filter(
fun(C) ->
($0 =< C) andalso (C =< $9)
end,
Number
).
checksum([], _, Total) ->
Total;
checksum([H | ReversedNumber], odd, Total) ->
checksum(ReversedNumber, even, Total + H - $0);
checksum([H | ReversedNumber], even, Total) when H < $5 ->
checksum(ReversedNumber, odd, Total + (H - $0) * 2);
checksum([H | ReversedNumber], even, Total) when H >= $5 ->
checksum(ReversedNumber, odd, Total + ((H - $0) * 2) - 9).
valid(Number) ->
case is_numeric(Number) of
true ->
case filter_input(Number) of
Number2 = [_,_|_] ->
checksum(Number2) rem 10 == 0;
_ -> false
end;
_ -> false
end.
test_version() ->
2.
Version data entries
136 entries across 136 versions & 1 rubygems