Running Elixir’s Interactive Shell (iex) in Powershell

IEx is Elixir’s interactive shell, where you can type any Elixir expressions and get its result.

One issue you might come across when trying to use iex in Powershell, through a command e.g. iex -S mix, you might get the following error:

Invoke-Expression : A parameter cannot be found that matches parameter name 'S'.
At line:1 char:5
+ iex -S mix
+     ~~
    + CategoryInfo          : InvalidArgument: (:) [Invoke-Expression], ParameterBindingException
    + FullyQualifiedErrorId : NamedParameterNotFound,Microsoft.PowerShell.Commands.InvokeExpressionCommand

The problem is that iex is an alias in Powershell, for Invoke-Expression

PS C:\Workspace> Get-Command iex

CommandType     Name                       Version    Source
-----------     ----                       -------    ------
Alias           iex -> Invoke-Expression

Solution

To overcome this problem you simply use iex.bat instead of iex in Powershell. So, if you type iex.bat -S mix, you ‘ll get the following output:

PS C:\Workspace\Research\elixir\physics> iex.bat -S mix
Eshell V8.0  (abort with ^G)
Compiling 1 file (.ex)
Generated physics app
Interactive Elixir (1.4.1) - press Ctrl+C to exit (type h() ENTER for help)
iex(1)>

and you are ready to start working with elixir’s interactive shell.