Designing Elixir Systems With OTP

Primitive Types

Elixir supports a short list of primitive types, including booleans, floats, integers, atoms, and references. We don’t have much guidance for primitive types since for the most part they behave much like they do in other languages. We do have a couple of thoughts, though.

Numbers

Elixir numbers are integers and floats. Remember that floats are estimates.^[4] Consider this example:

iex(1)> 0.1 + 0.2
0.30000000000000004

Therefore, unless you’re in a position to profit illegally, prefer integers or decimals over floats when you can. Here are a few places that strategy might make, er, sense:

• If you have a choice, store money in cents.
• Use div() and rem() to get integer division rather than /.
• make_ref() is a function that returns ...