我有简单的DSL，我从rails中添加了deep_merge gem，以合并包含其他哈希（:production => { :key1 =>["value1"],:group1 => { :key2 =>["value2"] } }）的哈希。 但是当我想输出合并键的值时，ruby输出nil。

Configus.rb：

class Configus
  class InHash
    attr_reader :inner_hash

    def initialize
      @inner_hash = {}
    end

    def method_missing(name,*args,&block)
      if block_given?
        context = InHash.new
        context.instance_eval &block
        @inner_hash[name] = context
      elsif args.empty?
        @inner_hash[name]
      else
        @inner_hash[name] = args
      end
    end
  end

  def self.config(environment,parent = nil,&block)
    in_hash = InHash.new
    in_hash.instance_eval &block
    keys = in_hash.inner_hash.keys
    index = keys.find_index(environment)
    if parent && environment
      parent_hash = in_hash.inner_hash[parent]
      adopted_hash = in_hash.inner_hash[environment]
      merged_hash = parent_hash.deep_merge!(adopted_hash)
      in_hash
    elsif environment == keys[index]
      in_hash.inner_hash[environment]
    end
  end
end

Init.rb：

require "./configus"
require "pry"

#Binding.pry

config = Configus.config :staging,:production do
  production do
    key1 "value1"
    key2 "value2"
    group1 do
      key3 "value3"
      key4 "value4"
    end
  end

  staging do
    key2 "new value2"
    group1 do
      key4 "new value4"
    end
  end
end

puts config.key1

没有父母的情况下撬出输出（例如：:staging = adopted_hash,:production = parent_hash）：

=> #<Configus::InHash:0x000056372547fd30
 @inner_hash=
  {:key1=>["value1"],:key2=>["value2"],:group1=>
    #<Configus::InHash:0x000056372547fbc8
     @inner_hash={:key3=>["value3"],:key4=>["value4"]}>}>

在育儿环境下撬动：

=> #<Configus::InHash:0x0000557f88a5f5e8
 @inner_hash=
  {:production=>
    #<Configus::InHash:0x0000557f88a5f1b0
     @inner_hash=
      {:key1=>["value1"],:group1=>#<Configus::InHash:0x0000557f88a5ed50 @inner_hash={:key3=>["value3"],:key4=>["value4"]}>,:deep_merge!=>
        [#<Configus::InHash:0x0000557f88a5ea08
          @inner_hash={:key2=>["new value2"],:group1=>#<Configus::InHash:0x0000557f88a5e5f8 @inner_hash={:key4=>["new value4"]}>}>]}>,:staging=>
    #<Configus::InHash:0x0000557f88a5ea08
     @inner_hash={:key2=>["new value2"],:group1=>#<Configus::InHash:0x0000557f88a5e5f8 @inner_hash={:key4=>["new value4"]}>}>}>