X-Git-Url: https://git.xandkar.net/?a=blobdiff_plain;f=compiler%2Fsrc%2Flib%2Ftiger%2Ftiger_env_type.ml;h=a2e719f37d5d8e315a63e4ce715ba18596d10e69;hb=e6e82c0866db4eb08f956b2582e5c2ed5399e986;hp=041d4213a64fce5a8f370aeb6e4ccb2e5edf1835;hpb=c0bdf964d389a2b9465fad44aa1f1f849c72140f;p=tiger.ml.git

diff --git a/compiler/src/lib/tiger/tiger_env_type.ml b/compiler/src/lib/tiger/tiger_env_type.ml
index 041d421..a2e719f 100644
--- a/compiler/src/lib/tiger/tiger_env_type.ml
+++ b/compiler/src/lib/tiger/tiger_env_type.ml
@@ -15,13 +15,15 @@ type t =
   | String
   | Record of
       { unique : unique
-      ; fields : (Symbol.t * t) list
+      ; fields : record_fields
       }
   | Array of
       { unique : unique
       ; ty     : t
       }
   | Name of Symbol.t * t option ref
+and record_fields =
+  (Tiger_symbol.t * t) list
 
 type env =
   (Symbol.t, t ) Map.t
@@ -43,30 +45,39 @@ let new_array ty =
 
 let is_equal t1 t2 =
   match t1, t2 with
+  | Name   (s1, _)       ,  Name   (s2, _)        -> Symbol.is_equal s1 s2
   | Record {unique=u1; _},  Record {unique=u2; _} -> u1 == u2
+  | Record _             ,  Nil                   -> true
+  | Nil                  ,  Record _              -> true
   | Array  {unique=u1; _},  Array  {unique=u2; _} -> u1 == u2
   | t1                   , t2                     -> t1 =  t2
   (* The above pattern matching is "fragile" and I'm OK with it.
    * TODO: Can we ignore the warning locally?
    * *)
 
-let is_record = function
+let is_int t =
+  t = Int
+
+let is_string t =
+  t = String
+
+let is_array = function
   | Unit
   | Int
   | String
   | Name _
-  | Array  _ -> false
-  | Nil  (* nil belongs to ANY record *)
-  | Record _ -> true
+  | Nil
+  | Record _ -> false
+  | Array  _ -> true
 
-let is_int = function
+let is_record = function
   | Unit
-  | Nil
+  | Int
   | String
   | Name _
-  | Record _
+  | Nil
   | Array  _ -> false
-  | Int      -> true
+  | Record _ -> true
 
 let is_name = function
   | Unit
@@ -77,6 +88,30 @@ let is_name = function
   | Array  _ -> false
   | Name _   -> true
 
+let if_record t ~f ~otherwise =
+  match t with
+  | Record {fields; _} ->
+      f fields
+  | Unit
+  | Int
+  | String
+  | Name _
+  | Nil
+  | Array  _ ->
+      otherwise ()
+
+let if_array t ~f ~otherwise =
+  match t with
+  | Array {ty=t; _} ->
+      f t
+  | Unit
+  | Int
+  | String
+  | Name _
+  | Nil
+  | Record _ ->
+      otherwise ()
+
 let to_string = function
   | Unit               -> "unit"
   | Nil                -> "nil"