---
title: IEx
---
## IEx (Interactive Elixir Mode)
`iex` is *interactive Elixir*. It is a command-line interface to Elixir or your Elixir application.
`iex` is [REPL][REPL] that allows you to evaluate any statement with immediate feedback. There's no need for compiling any code or putting your code into a script file.
### Getting started
With Elixir installed, you should be able to simply run `iex` from your shell and find something like the following:
```shell
$ iex
Erlang/OTP 21 [erts-10.1.1] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:1] [hipe] [dtrace]
Interactive Elixir (1.7.3) - press Ctrl+C to exit (type h() ENTER for help)
iex(1)>
```
Now you can evaluate any valid Elixir statement followed by pressing ENTER and the result will be displayed on the next line.
```shell
iex(1) 1 + 1
2
```
### Tab completion
`iex` features tab completion. Aside from saving keystrokes, it allows you to see which functions and submodules are available.
For example, type DaTAB. It should expand to `Date`. Now press TAB again and you'll see two options: `Date` and `DateTime` as both modules start with `Date`.
Now let's say you want to use a function in the `Date` module but can't remember the name or arity. Type a . after the module name, press TAB and you'll see all available functions in the module.
```shell
iex(3)> Date.
Range add/2 compare/2
convert!/2 convert/2 day_of_week/1
days_in_month/1 diff/2 from_erl!/1
from_erl!/2 from_erl/1 from_erl/2
from_iso8601!/1 from_iso8601!/2 from_iso8601/1
from_iso8601/2 leap_year?/1 months_in_year/1
new/3 new/4 range/2
to_erl/1 to_iso8601/1 to_iso8601/2
to_string/1 utc_today/0 utc_today/1
```
You'll notice that `Range` at the top of the list. This is a submodule of `Date`. You can continue tab completion with submodules or functions.
### Exiting
To exit `iex`, press CTRL+C to bring up the break menu. You can press a, ENTER or just press CTRL+C a second time to exit.
### Cancelling statement evaluation
If you're writing a complex statement and make a mistake, you may be tempted to press CTRL+C to cancel statement evaluation as you would in a standard shell. Unfortunately that won't work in `iex` as it just brings up the break menu.
`iex` allows a magic comment of `#iex:break` to be typed any time, followed by ENTER to abort statement evaluation.
Let's take this example where you are constructing a map and forgot a quote partway through. You pressed enter to evaluate and get stuck at a statement continuation prompt and you want to abort. Just type `#iex:break` followed by ENTER:
```shell
iex(1)> %{ user: "tom, roles: ["admin", "manager"] }
...(1)> #iex:break
** (TokenMissingError) iex:1: incomplete expression
iex(1)>
```
### Loading your Mix application
`iex` can load a script during startup. A common use for this is loading your `mix.exs` script so that your `iex` session contains your whole application and its dependencies loaded and ready to work with.
```shell
$ iex -S mix
```
#### More Information:
* [Official Elixir Documentation](https://elixir-lang.org/getting-started/introduction.html#interactive-mode)
[REPL]: https://en.wikipedia.org/wiki/Read%E2%80%93eval%E2%80%93print_loop