Learn the basics of Elixir, along with advanced concepts such as OTP servers and multiple processes.

Become an Elixir Programmer

In this module, we’ll learn everything we need to know to start working with Elixir, including processing collections, using multiple tools, and working with OTP servers. Programmers usually learn by writing code, and that’s exactly how this module will also work. We'll practice a lot of coding examples that will help us get a strong grip on Elixir.

Master the Art of Programming in Elixir

We can override the unary and binary operators in Elixir using macros. To do so, we need to remove any existing definition first.

# Overriding operators example

For example, the operator `+` (which adds two numbers) is defined in the `Kernel` module. To remove the `Kernel` definition and substitute our own, we’d need to do something like the following code which redefines addition to concatenate the string representation of the left and right arguments.
```elixir
defmodule Operators do
  defmacro a + b do
    quote do
      to_string(unquote(a)) <> to_string(unquote(b))
    end
  end
end

defmodule Test do
  IO.puts(123 + 456)             #=> "579"
  import Kernel, except: [+: 2]
  import Operators
  IO.puts(123 + 456)             #=> "123456"
end

IO.puts(123 + 456)               #=> "579"
```
Note that the macro’s definition is lexically scoped—the `+` operator is overridden from the point when we import the `Operators` module through the end of the module that imports it. We could also have done the import inside a single method, and the scoping would be just that method.

Run the `c "operators.ex"` command to execute the code below:


Learn how to override operators using macros.

Macros and Operators