Class: Weight

Inherits:
Object
  • Object
show all
Includes:
Comparable, Configuration
Defined in:
lib/weight.rb,
lib/weight/version.rb

Defined Under Namespace

Modules: Configuration

Constant Summary collapse

VERSION = 
"0.0.1"

Instance Method Summary collapse

Methods included from Configuration

allowed_units, configure, default_unit, default_unit=

Constructor Details

#initialize(value = 0, unit = default_unit) ⇒ Weight

Class contructor

Parameters:

  • value (Int) (defaults to: 0) —

    The weight of the object

  • unit (String) (defaults to: default_unit) —

    The unit in which the value is expressed. Currently supports ‘lb’ and ‘kg’

Raises:

  • (TypeError) —

    When weight is negative



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# File 'lib/weight.rb', line 12

def initialize(value = 0, unit = default_unit)
  self.value, self.unit = value, unit
end

Instance Method Details

#*(other) ⇒ Weight

Multiplication operation

Parameters:

  • other (Weight) —

    The other weight to multiply by the current one

Returns:

  • (Weight) —

    The product of the two weights

Raises:

  • (TypeError) —

    When the argument passed is not a Weight



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# File 'lib/weight.rb', line 89

def *(other)
  raise TypeError, 'You can only multiply a weight by a number' unless other.is_a?(Numeric)
  self.class.new(value * other, unit)
end

#+(other) ⇒ Weight

Addition operation

Parameters:

  • other (Weight) —

    The other weight to add to the current one

Returns:

  • (Weight) —

    The sum of the two weights

Raises:

  • (TypeError) —

    When the argument passed is not a Weight



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# File 'lib/weight.rb', line 52

def +(other)
  raise TypeError, 'You can only add weights' unless other.is_a?(Weight)
  self.class.new(raw_data_in_kg + other.to_kgs, :kg)
end

#-(other) ⇒ Weight

Substract operation

Parameters:

  • other (Weight) —

    The other weight to substract to the current one

Returns:

  • (Weight) —

    The substraction of the two weights

Raises:

  • (TypeError) —

    When the argument passed is not a Weight



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# File 'lib/weight.rb', line 80

def -(other)
  raise TypeError, 'You can only substract weights' unless other.is_a?(Weight)
  self.class.new(raw_data_in_kg - other.to_kgs, :kg)
end

#/(other) ⇒ Weight

Division operation

Parameters:

  • other (Weight) —

    The weight to divide the current one by

Returns:

  • (Weight) —

    The result of the operation

Raises:

  • (TypeError) —

    When the argument passed is not a Weight



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# File 'lib/weight.rb', line 98

def /(other)
  raise TypeError, 'You can only divide a weight by a number' unless other.is_a?(Numeric)
  self.class.new(value / other, unit)
end

#<=>(other) ⇒ -1, ...

Comparison operator

Parameters:

  • other (Weight) —

    The other weight to compare to the current one

Returns:

  • (-1, 0, 1)

Raises:

  • (TypeError) —

    When the argument passed is not a Weight



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# File 'lib/weight.rb', line 71

def <=>(other)
  raise TypeError, 'You can only compare weights' unless other.is_a?(Weight)
  self.to_kgs <=> other.to_kgs
end

#==(other) ⇒ Bool

Comparison operator

Parameters:

  • other (Weight) —

    The other weight to compare to the current one

Returns:

  • (Bool) —

    True if both of the objects have the same weight. False otherwise

Raises:

  • (TypeError) —

    When the argument passed is not a Weight



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# File 'lib/weight.rb', line 62

def ==(other)
  raise TypeError, 'You can only compare weights' unless other.is_a?(Weight)
  raw_data_in_kg.round(4) == other.to_kgs
end

#to_f ⇒ Float

Returns the weight converted to pounds

Returns:

  • (Float) —

    The weight in pounds



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# File 'lib/weight.rb', line 38

def to_f
  value.to_f.round(4)
end

#to_i ⇒ Int

Returns the weight in pounds rounded to the closest integer

Returns:

  • (Int) —

    The weight in pounds rounded



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# File 'lib/weight.rb', line 44

def to_i
  value.round
end

#to_kgs ⇒ Float

Returns the weight converted to pounds

Returns:

  • (Float) —

    The weight in pounds



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# File 'lib/weight.rb', line 26

def to_kgs
  raw_data_in_kg.round(4)
end

#to_lbs ⇒ Float

Returns the weight converted to kilograms

Returns:

  • (Float) —

    The weight in kilograms



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# File 'lib/weight.rb', line 32

def to_lbs
  (raw_data_in_kg * pounds_per_kilogram).round(4)
end

#unit ⇒ Object 



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# File 'lib/weight.rb', line 20

def unit
  @input_unit
end

#value ⇒ Object 



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# File 'lib/weight.rb', line 16

def value
  @input_value
end