hphp/hack/src/typing/typing_instantiate.mli

   1 (**
   2  * Copyright (c) 2015, Facebook, Inc.
   3  * All rights reserved.
   4  *
   5  * This source code is licensed under the BSD-style license found in the
   6  * LICENSE file in the "hack" directory of this source tree. An additional grant
   7  * of patent rights can be found in the PATENTS file in the same directory.
   8  *
   9  *)
  10
  11 open Typing_defs
  12
  13 (*****************************************************************************)
  14 (* Types *)
  15 (*****************************************************************************)
  16
  17 type subst
  18
  19 (*****************************************************************************)
  20 (* Builds a substitution out of a list of type parameters and a list of types.
  21  *
  22  * Typical use-case:
  23  *   class Y<T> { ... }
  24  *   class X extends Y<int>
  25  *
  26  * To build the type of X, we to replace all the occurrences of T in Y by int.
  27  * The function make_subst, builds the substition (the map associating types
  28  * to a type parameter name), in this case, it would build the map(T => int).
  29  *)
  30 (*****************************************************************************)
  31
  32 val make_subst: decl tparam list -> decl ty list -> subst
  33
  34 (*****************************************************************************)
  35 (* Primitive instantiating a type.
  36  * TODO: explain what instantiation is about.
  37  *)
  38 (*****************************************************************************)
  39
  40 val instantiate     : subst -> decl ty -> decl ty
  41 val instantiate_ce  : subst -> class_elt -> class_elt
  42 val instantiate_typeconst :
  43   subst -> typeconst_type -> typeconst_type