Settings Pex (pex v0.1.0)

This is how to use Pex

examples

Examples

automatic-result-tuples

Automatic result tuples

iex> %{hello: "world"} |> Map.get(:hello)
{:ok, "world"}

pipe-into-maps

Pipe into maps

iex> "world" |> %{hello: &1}
{:ok, %{hello: "world"}}

iex> :hello |> %{&1 => "world"}
{:ok, %{hello: "world"}}

pipe-into-lists

Pipe into lists

iex> 2 |> [1, &1, 3]
{:ok, [1, 2, 3]}

iex> 1 |> [&1 | [2, 3]]
{:ok, [1, 2, 3]}

iex> [2, 3] |> [1 | &1]
{:ok, [1, 2, 3]}

pipe-into-a-specific-function-parameter-instead-of-the-first

Pipe into a specific function parameter (instead of the first)

iex> %{hello: "world"}
...> |> Map.get(:hello)
...> |> Map.put(%{}, :goodbye, &1)
{:ok, %{goodbye: "world"}}

pipe-into-function-definition

Pipe into function definition

iex> %{hello: "world"}
...> |> Map.get(:hello)
...> |> fn value -> "hello " <> value end
{:ok, "hello world"}

skip-over-error-tuples

Skip over error tuples

iex> {:error, "Something went wrong"}
...> |> Map.get(:hello)
...> |> Map.put(%{}, :goodbye, &1)
{:error, "Something went wrong"}

transform-error-tuples-with

Transform error tuples (with ~>)

iex> assert {:error, "Something went wrong"}
...> |> Tuple.to_list
...> <~ fn error -> error <> ", more information" end
{:error, "Something went wrong, more information"}

iex> {:error, "Something went wrong"}
...> <~ fn _ -> {:ok, "recovered"} end
...> |> fn _ -> "hello world" end
{:ok, "hello world"}

inspect-both-result-tuples-with-simplified-labels

Inspect both result tuples (with simplified labels)

iex> ExUnit.CaptureIO.capture_io(fn ->
...>  {:error, "Something went wrong"}
...>  |> IO.inspect("error")             # With label
...>  <~ fn _ -> {:ok, "recovered"} end
...>  |> IO.inspect                      # Without label
...> end)
"""
error: {:error, "Something went wrong"}
{:ok, "recovered"}
"""

catch-thrown-values

Catch thrown values

iex> %{hello: "world"}
...> |> Map.get(:hello)
...> |> fn _ -> throw("Something went wrong") end
{:error, "Something went wrong"}

rescue-exceptions

Rescue exceptions

iex> %{hello: "world"}
...> |> Map.get(:hello)
...> |> fn _ -> raise("Something went wrong") end
{:error, %RuntimeError{message: "Something went wrong"}}