Programmer Passport: Elixir

Characters Are Code Points

The process of making code safe for multiple languages at once is internationalization. If you’re familiar with it, you know that every single character in a string is called a code point. In Elixir, a code point is represented with a number. Here’s how it works:

iex(18)> ?a
97

If this were the only surprising behavior, I’d probably let you read about it yourself, but there’s a strange remnant from Elixir’s dependence on Erlang. Namely, Elixir can’t always tell the difference between lists of numbers and character lists!

Here’s what I mean:

iex(22)> [99, 97, 116]
'cat'

This happens because Erlang can’t tell the difference between a list of integers and a list of characters, so it guesses. Sometimes these lists ...