> For the complete documentation index, see [llms.txt](https://ploegert.gitbook.io/til/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ploegert.gitbook.io/til/programmy/elixir/when-things-dont-match-the-with-statements.md).

# When Things Don't Match The With Statements

You set up a series of match statements in a `with` construct as a way of avoiding a bunch of nested if statements. Inevitably you will be passing data through that doesn't meet all of the match criteria. By default, the `with` construct will short circuit and your program will continue from there.

You can, however, take more control over how you handle the *failure* cases by employing an `else` block. The `else` block works a lot like a case statement.

```elixir
with %{status_code: 200, body: body} <- HTTPoison.get!(url),
     {:ok, decoded_body} <- Poison.decode(body) do
  {:ok, decoded_body}
else
  %{status_code: 401} ->
    reauthenticate()
  _ ->
    log_error()
end
```

Here we are able to anticipate a *failure* case and respond accordingly. For everything else, we have a generic action that we take.

See the [docs for `with`](https://hexdocs.pm/elixir/Kernel.SpecialForms.html#with/1) for more details.