lib/mlton/basic/pair.fun

   1 (* Copyright (C) 1999-2005 Henry Cejtin, Matthew Fluet, Suresh
   2  *    Jagannathan, and Stephen Weeks.
   3  *
   4  * MLton is released under a BSD-style license.
   5  * See the file MLton-LICENSE for details.
   6  *)
   7 (*-------------------------------------------------------------------*)
   8 (*                               Pair                                *)
   9 (*-------------------------------------------------------------------*)
  10
  11 functor Pair(structure X: T
  12              structure Y: T): PAIR =
  13 struct
  14
  15 structure X = X
  16 structure Y = Y
  17
  18 type t = X.t * Y.t
  19
  20 fun equals((x, y), (x', y')) = X.equals(x, x') andalso Y.equals(y, y')
  21
  22 local open Layout
  23 in fun layout(x, y) =
  24    paren(seq[X.layout x, str ", ", Y.layout y])
  25 end
  26 (*
  27 fun output((x, y), out) =
  28    let val print = Out.outputc out
  29    in (print "(" ;
  30        X.output(x, out) ;
  31        print ", " ;
  32        Y.output(y, out) ;
  33        print ")")
  34    end
  35   *)
  36 end