Class: Struct

Inherits:
Object
  • Object
show all
Defined in:
lib/casual_support/struct/from_h.rb,
lib/casual_support/struct/assign_attributes.rb

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.from_h(attributes) ⇒ Struct

Constructs an instance of a subclass of Struct, and assigns the values of the given attributes Hash to the instance.

This method is intended for use only with subclasses of Struct which do not alter the default signature of the initialize method. Specifically, the initialize method must support invocation with no arguments.

Examples:

Point = Struct.new(:x, :y, :z)

Point.from_h(x: 10, y: 20, z: 30)  # == Point.new(10, 20, 30)

Parameters:

Returns:

See Also:



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# File 'lib/casual_support/struct/from_h.rb', line 22

def self.from_h(attributes)
  raise "Struct.from_h is for use only with subclasses of Struct" if self == Struct
  self.new.assign_attributes(attributes)
end

Instance Method Details

#assign_attributes(new_attributes) ⇒ self

Assigns values in the given Hash to corresponding attributes of the Struct. Both Symbol keys and String keys are accepted. Keys which don’t correspond to an attribute of the Struct are ignored. Mutates the Struct and returns it.

Examples:

Point = Struct.new(:x, :y, :z)
point = Point.new(10, 20, 30)

point.assign_attributes(y: 30, z: 50).to_h  # == { x: 10, y: 30, z: 50 }

Parameters:

Returns:

  • (self) 


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# File 'lib/casual_support/struct/assign_attributes.rb', line 16

def assign_attributes(new_attributes)
  ms = self.members
  new_attributes.each do |k, v|
    m = k.to_sym
    self[m] = v if ms.include?(m)
  end
  self
end