1 files changed, 67 insertions, 0 deletions
diff --git a/src/expressions/shift_expr.ml b/src/expressions/shift_expr.ml
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+++ b/src/expressions/shift_expr.ml
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+(*
+This file is part of licht.
+
+licht is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+licht is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with licht.  If not, see <http://www.gnu.org/licenses/>.
+*)
+
+module Shift_Ref = struct
+
+  type 'a t = (int * int) -> ScTypes.Refs.t
+  type 'a obs = (int * int) -> ScTypes.Refs.t
+
+  let _shift (vector_x, vector_y) ((x, y), (fixed_x, fixed_y)) =
+    let x' = if fixed_x then x else x + vector_x
+    and y' = if fixed_y then y else y + vector_y in
+      (x', y'), (fixed_x, fixed_y)
+
+  let cell t shift =
+    ScTypes.Refs.cell (_shift shift t)
+
+
+  let range c1 c2 shift =
+    ScTypes.Refs.range (_shift shift c1) (_shift shift c2)
+
+  let observe elem shift = elem shift
+
+end
+
+module Shift_Expr = struct
+
+  type t = (int * int) -> ScTypes.Expr.t
+  type obs =  (int * int) -> ScTypes.Expr.t
+
+  module R = Shift_Ref
+  module T = Id_type
+
+  let observe f x = f x
+
+  let value t vector = ScTypes.Expr.value (T.observe t)
+
+  let ref r vector = ScTypes.Expr.ref (R.observe r vector)
+
+  let call0 ident vector = ScTypes.Expr.call0 ident
+
+  let call1 ident p1 vector = ScTypes.Expr.call1 ident (observe p1 vector)
+
+  let call2 ident p1 p2 vector = ScTypes.Expr.call2  ident (observe p1 vector) (observe p2 vector)
+
+  let call3 ident p1 p2 p3 vector = ScTypes.Expr.call3 ident (observe p1 vector) (observe p2 vector) (observe p3 vector)
+
+  let expression e vector = ScTypes.Expr.expression (observe e vector)
+
+  let callN ident (params: t list) vector = ScTypes.Expr.callN ident (List.map (fun x -> observe x vector) params)
+
+end
+
+include Shift_Expr