Allows for reverse merging where its the keys in the calling hash that wins over those in the other_hash. This is particularly useful for initializing an incoming option hash with default values:

  def setup(options = {})
    options.reverse_merge! :size => 25, :velocity => 10
  end

The default :size and :velocity is only set if the options passed in doesn’t already have those keys set.

Methods
Public Instance methods
reverse_merge(other_hash)
This method is also aliased as reverse_update
    # File vendor/rails/activesupport/lib/active_support/core_ext/hash/reverse_merge.rb, line 13
13:         def reverse_merge(other_hash)
14:           other_hash.merge(self)
15:         end
reverse_merge!(other_hash)
    # File vendor/rails/activesupport/lib/active_support/core_ext/hash/reverse_merge.rb, line 17
17:         def reverse_merge!(other_hash)
18:           replace(reverse_merge(other_hash))
19:         end
reverse_update(other_hash)

Alias for reverse_merge