+abstract class Buffer
+ super Text
+
+ # Modifies the char contained at pos `index`
+ #
+ # DEPRECATED : Use self.chars.[]= instead
+ fun []=(index: Int, item: Char) is abstract
+
+ # Adds a char `c` at the end of self
+ #
+ # DEPRECATED : Use self.chars.add instead
+ fun add(c: Char) is abstract
+
+ # Clears the buffer
+ fun clear is abstract
+
+ # Enlarges the subsequent array containing the chars of self
+ fun enlarge(cap: Int) is abstract
+
+ # Adds the content of string `s` at the end of self
+ fun append(s: String) is abstract
+
+ redef fun chars: BufferCharView is abstract
+end
+