class RubyXL::Parser

def self.parse(file_path, opts = {})

def self.parse(file_path, opts = {})
  self.new(opts).parse(file_path)
end

def initialize(opts = {})

However, using this option will result in date-formatted cells being interpreted as numbers.
+:data_only+ allows only the sheet data to be parsed, so as to speed up parsing.
def initialize(opts = {})
  @opts = opts
end

def parse(xl_file_path)

def parse(xl_file_path)
  root = RubyXL::WorkbookRoot.parse_file(xl_file_path, @opts)
  wb = root.workbook
  wb.sheets.each_with_index { |sheet, i|
    sheet_obj = wb.relationship_container.related_files[sheet.r_id]
    wb.worksheets[i] = sheet_obj # Must be done first so the sheet becomes aware of its number
    sheet_obj.workbook = wb
    sheet_obj.sheet_name = sheet.name
    sheet_obj.sheet_id = sheet.sheet_id
    sheet_obj.state = sheet.state
  }
  wb
end