Ruby: merge nested hash

Question

I would like to merge a nested hash.

a = {:book=>
    [{:title=>\"Hamlet\",
      :author=>\"William Shakespeare\"
      }]}

b = {:book=>
    [{         


        

Answer 1

All answers look to me overcomplicated. Here's what I came up with eventually:

# @param tgt [Hash] target hash that we will be **altering**
# @param src [Hash] read from this source hash
# @return the modified target hash
# @note this one does not merge Arrays
def self.deep_merge!(tgt_hash, src_hash)
  tgt_hash.merge!(src_hash) { |key, oldval, newval|
    if oldval.kind_of?(Hash) && newval.kind_of?(Hash)
      deep_merge!(oldval, newval)
    else
      newval
    end
  }
end

P.S. use as public, WTFPL or whatever license