哈姆语法 - 更好的书写方式？

Question

必须有书面的更好的方法这个 - 我只是不知道如何（使用staticmatic） -

- if current_page.include? "0.html" 
    - @current_index = 1 
- if current_page.include? "1.html" 
    - @current_index = 2 
- if current_page.include? "2.html" 
    - @current_index = 3 
- if current_page.include? "3.html" 
    - @current_index = 4 
- if current_page.include? "4.html" 
    - @current_index = 5 
- if current_page.include? "5.html" 
    - @current_index = 6 
- if current_page.include? "6.html" 
    - @current_index = 7 
- if current_page.include? "7.html" 
    - @current_index = 8 
- if current_page.include? "8.html" 
    - @current_index = 9 
- if current_page.include? "9.html" 
    - @current_index = 10 
- if current_page.include? "10.html" 
    - @current_index = 11 
- if current_page.include? "11.html" 
    - @current_index = 12 

Answer 1

- 0.upto(11) do |n| 
    - if current_page.include? "#{n}.html" 
    - @current_index = n + 1 

Answer 2

- @current_index = current_page[/(\d+)\.html/, 1].to_i + 1