The overrides system allows defining component defaults while also enabling deep customization and ad-hoc overrides of Pyro component props. This allows consumers of your component library to trivially and granularly modify your presets.

A Pyro.Component flags attrs with overridable, then leverages assign_overridables/1 to reference overrides set in these presets/custom override modules and load them as defaults.

Configure your app with:

config :pyro, :overrides,
  [MyApp.Overrides]

Then, define your overrides in your custom module:

defmodule MyApp.Overrides do
  @moduledoc false
  use Pyro.Overrides

  override MyAppWeb.CoreComponents, :back do
    set :class, "text-lg font-black"
    set :icon_kind, :outline
    set :icon_name, :arrow_left
  end
end

The overrides will be merged left-to-right, returning the value in the first module that sets a given key. So in the above example, the <Core.back> component will have an icon_name default of :arrow_left, since the MyApp.Overrides was the first module in the list to provide that key:

• You only need to define what you want to override from the other defaults
• You can use any number of :overrides modules, though it is probably best to only use only 1-3 to keep things simple/efficient
• If no modules define the value, it will simply be nil
• If assign_overridables/1 is called on the component with the required: true attr option, an error will be raised if no configured overrides define a default