Module: Revector::Utility

Defined in:

lib/revector/utility.rb

Defined Under Namespace

Modules: Keys

Constant Summary

TryFetchOrBlank =

hash = { a: 1, b: { c: 2 }, d: [{ e: 3 }] } Utility::TryFetchOrBlank.(hash, ‘d..e’) ““

->(data, *arr_keys) do
  reducer = ->(memo, key) do
    symbol_keys = *Keys.to_dig(key)

    deep_value = symbol_keys.reduce(memo) do |acc, attr|
      acc = acc.compact

      case acc
      in [::Integer, _] | [::String, _] | Integer
        acc[attr]
      in ::Array
        case acc
        in [::Hash, _]
          case attr
          in ::Integer
            acc&.dig(attr)
          else
            acc&.flat_map { |x| x&.dig(attr) }
          end
        else
          case attr
          in ::Integer | ::String
            acc&.dig(attr)
          else
            acc&.flat_map { |x| x.respond_to?(:dig) ? x&.dig(attr) : x }
          end
        end
      in ::Hash
        acc&.dig(attr)
      else
        acc
      end
    end

    deep_value
  rescue StandardError => e
    nil
  end

  arr_keys.reduce(data, &reducer)
end