Class: Measured::UnitSystem

Inherits:
Object
  • Object
show all
Defined in:
lib/measured/unit_system.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(units) ⇒ UnitSystem

Returns a new instance of UnitSystem.



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# File 'lib/measured/unit_system.rb', line 4

def initialize(units)
  @units = units.map { |unit| unit.with_unit_system(self) }
end

Instance Attribute Details

#units ⇒ Object (readonly)

Returns the value of attribute units.



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# File 'lib/measured/unit_system.rb', line 2

def units
  @units
end

Instance Method Details

#convert(value, from:, to:) ⇒ Object

Raises:



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# File 'lib/measured/unit_system.rb', line 35

def convert(value, from:, to:)
  conversion = conversion_table.fetch(from.name, {})[to.name]

  raise Measured::UnitError, "Cannot find conversion entry from #{from} to #{to}" unless conversion

  value.to_r * conversion
end

#unit?(name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/measured/unit_system.rb', line 20

def unit?(name)
  unit = unit_for(name)
  unit ? unit.name == name.to_s : false
end

#unit_for(name) ⇒ Object 



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# File 'lib/measured/unit_system.rb', line 25

def unit_for(name)
  unit_name_to_unit[name.to_s]
end

#unit_for!(name) ⇒ Object

Raises:



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# File 'lib/measured/unit_system.rb', line 29

def unit_for!(name)
  unit = unit_for(name)
  raise Measured::UnitError, "Unit '#{name}' does not exist" unless unit
  unit
end

#unit_names ⇒ Object 



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# File 'lib/measured/unit_system.rb', line 12

def unit_names
  @unit_names ||= @units.map(&:name).sort
end

#unit_names_with_aliases ⇒ Object 



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# File 'lib/measured/unit_system.rb', line 8

def unit_names_with_aliases
  @unit_names_with_aliases ||= @units.flat_map(&:names).sort
end

#unit_or_alias?(name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/measured/unit_system.rb', line 16

def unit_or_alias?(name)
  !!unit_for(name)
end