Implementing Ruby's lonely operator using Elixir's custom infix function

README.md

Implementing Ruby's lonely operator using Elixir's custom infix function

iex> import ViewHelper
iex> user = %{name: "Imran", address: %{postcode: 33160}}
iex> user ~> :name
# "Imran"
iex> user ~> :address ~> :postcode
# 33160
iex> user ~> :address ~> :country
# nil

Update

Just found out from benwilson that [] implements the access protocol, so it would return nil even when accessing from nil.

Using access:

iex> user = %{name: "imran"}
iex> user[:name][:address][:postcode]
# nil

OR if you want the same syntax as above
iex> user |> Access.get(:name) |> Access.get(:postcode)
# nil

OR use get_in DUH!

Rewrote to just use the Access module

Update 2

Use back old implementation because Access protocol is not implemented on struct unless explicitly derived. Rightly so.

view_helper.ex

defmodule ViewHelper do
  def left ~> right do
    try_in(left, right)
  end
  
  defp try_in(nil, _keys), do: nil		
  defp try_in(result, []), do: result		
  defp try_in(struct, [head|tail]), do: try_in(Map.get(struct, head), tail)		
  defp try_in(struct, key), do: Map.get(struct, key)
end