new

Struct.new( [aString] [, aSym]+> ) â StructClass
Struct.new( [aString] [, aSym]+> ) {|StructClass| block } â StructClass
StructClass.new(arg, ...) â obj
StructClass[arg, ...] â obj
Class Public methods

Creates a new class, named by aString, containing accessor methods for the given symbols. If the name aString is omitted, an anonymous structure class will be created. Otherwise, the name of this struct will appear as a constant in class Struct, so it must be unique for all Structs in the system and should start with a capital letter. Assigning a structure class to a constant effectively gives the class the name of the constant.

If a block is given, it will be evaluated in the context of StructClass, passing StructClass as a parameter.

Customer = Struct.new(:name, :address) do
  def greeting
    "Hello #{name}!"
  end
end
Customer.new("Dave", "123 Main").greeting  # => "Hello Dave!"

Struct::new returns a new Class object, which can then be used to create specific instances of the new structure. The number of actual parameters must be less than or equal to the number of attributes defined for this class; unset parameters default to nil. Passing too many parameters will raise an ArgumentError.

The remaining methods listed in this section (class and instance) are defined for this generated class.

# Create a structure with a name in Struct
Struct.new("Customer", :name, :address)    #=> Struct::Customer
Struct::Customer.new("Dave", "123 Main")   #=> #<struct Struct::Customer name="Dave", address="123 Main">

# Create a structure named by its constant
Customer = Struct.new(:name, :address)     #=> Customer
Customer.new("Dave", "123 Main")           #=> #<struct Customer name="Dave", address="123 Main">
doc_ruby_on_rails
2015-05-16 05:06:08
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