Class: Bookland::ISBN

Inherits:

EAN

• Object
• Identifier
• EAN
• Bookland::ISBN

Defined in:

lib/bookland/isbn.rb

Constant Summary

PREFIXES =

[%w(9 7 8), %w(9 7 9)]

Constants inherited from EAN

EAN::WEIGHTS

Instance Attribute Summary

Attributes inherited from Identifier

#digits

Instance Method Summary

• #valid? ⇒ Boolean

Methods inherited from EAN

calculate_checksum_digit

Methods inherited from Identifier

#==, calculate_checksum_digit, #checksum_digit, #data_digits, #initialize, #to_s, valid?

Constructor Details

This class inherits a constructor from Bookland::Identifier

Instance Method Details

#valid? ⇒ Boolean

Returns:

• (Boolean)

# File 'lib/bookland/isbn.rb', line 5

def valid?
  PREFIXES.include?(digits[0, 3]) && super
end