Module: Gemmy::Patches::HashPatch::InstanceMethods::Rekey

Defined in:
lib/gemmy/patches/hash_patch.rb

Instance Method Summary collapse

Instance Method Details

#rekey(key_map = nil, &block) ⇒ Object

facets rekey according to a block, i.e. 1.rekey &:to_s

Raises:

  • (ArgumentError) 


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# File 'lib/gemmy/patches/hash_patch.rb', line 97

def rekey(key_map=nil, &block)
  raise ArgumentError, "argument or block" if key_map && block

  if !(key_map or block)
    block = lambda{|k| k.to_sym}
  end

  if block
    hash = dup.clear
    if block.arity.abs == 1
      each_pair do |k, v|
        hash[block[k]] = v     #hash[block[k] || k] = v
      end
    else
      each_pair do |k, v|
        hash[block[k,v]] = v   #hash[block[k,v] || k] = v
      end
    end
  else
    #hash = dup.clear  # to keep default_proc
    #(keys - key_map.keys).each do |key|
    #  hash[key] = self[key]
    #end
    #key_map.each do |from, to|
    #  hash[to] = self[from] if key?(from)
    #end
    hash = dup  # to keep default_proc
    key_map.each_pair do |from, to|
      hash[to] = hash.delete(from) if hash.key?(from)
    end
  end

  hash
end