Elixir has guard clauses, that I like to use heavily in conjunction with pattern matching:
defp _todo_hash(%{
title: title, # pattern matching
user_uid: user_uid,
date: date,
} = _attrs,
action
)
when is_binary(title) # guard clauses
and byte_size(title) > 0
and is_binary(user_uid)
and byte_size(user_uid) === 64
and is_binary(date)
and byte_size(date) === 10
do
# your code here
end
Now that I discovered the Domo library I am using it to have typed structs and then pattern match on them:
defmodule Tasks.Todos.Types.Event do
# @link https://hexdocs.pm/domo/Domo.html
use Domo
typedstruct do
field :type, :todo | :backlog
field :target, :todo | :backlog | :all
field :action, :add | :update | :move | :duplicate | :delete
field :origin, atom()
field :broadcast_topics, list(), default: []
field :context, map(), default: %{}
end
end
that are then used like this:
def broadcast_change(
{:ok, data} = result,
%Tasks.Todos.Types.Event{} = event
) do
# your code here
do
