method

transform_keys

v5.2.3 - Show latest stable - 0 notes - Class: Hash

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What's this?

transform_keys() public

Returns a new hash with all keys converted using the block operation.

hash = { name: 'Rob', age: '28' }

hash.transform_keys { |key| key.to_s.upcase } # => {"NAME"=>"Rob", "AGE"=>"28"}

If you do not provide a block, it will return an Enumerator for chaining with other methods:

hash.transform_keys.with_index { |k, i| [k, i].join } # => {"name0"=>"Rob", "age1"=>"28"}

Show source

# File activesupport/lib/active_support/core_ext/hash/keys.rb, line 14
  def transform_keys
    return enum_for(:transform_keys) { size } unless block_given?
    result = {}
    each_key do |key|
      result[yield(key)] = self[key]
    end
    result
  end

transform_keys

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