Ruby » Ruby master

Feature #15496

Updated by macdevign (Macdevign mac) almost 6 years ago

I could not find the a simple String api to extract the string between two string, and I notice that many face the same issue and endup rolling their own solutions (eg https://stackoverflow.com/questions/9661478/how-to-return-the-substring-of-a-string-between-two-strings-in-ruby).  

 Given that string "between" extraction is such a common operation, will adding a focused and simplified String method    make coding pleasant ? 

 This is my solution but probably someone can provide better and efficient implementation. 

 ~~~ ` 
   # self: String instance,  
   # from: first 'from' String   
   # to:    first 'to' String found after 'from' 
   # return string between from and to, which exclude the argument, nil otherwise. 

   def between(from, to) 
       from_idx = self.index(from)&.+(from.length) 
       if from_idx 
         to_idx = self.index(to, from_idx) 
         return self[from_idx...to_idx] if to_idx 
       end 
       nil 
     end 
 ~~~ ` 

 Test case 

 "Hello world".between("ell", "ld") => "o wor" 
 "Testing 123".between("Te", "123") => "sting " 

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