1structure Symreltab = Table(
2  type key = string * string
3  val ord = Portable.pair_compare (String.compare, String.compare)
4  fun pp (s1,s2) =
5    let
6      open HOLPP Portable
7    in
8      block CONSISTENT 0 [
9        add_string "(",
10        block CONSISTENT 1 [add_string (mlquote s1), add_string ",",
11                            add_break (1,0), add_string (mlquote s2)],
12        add_string ")"
13      ]
14    end
15);
16