crystal string token binding

string_token_binding.cr

 lib LibStrToken
   fun strtok( input : UInt8*, delim : UInt8*) : UInt8*
 end
 
 module Test
   class Run
     def string_token(str, del)
       io = IO::Memory.new(str.size)
       io << str
       split_tok = [] of String
       token = LibStrToken.strtok(io.to_s, del)
       split_tok << String.new(token)
       loop do
         token = LibStrToken.strtok(nil, del)
         break if  token.null?
         split_tok << String.new(token)
       end
       split_tok
     end
   end
 end
  
 puts Test::Run.new.string_token("This - is - split", " ")
 puts Test::Run.new.string_token("This - is - split", "-")