1 files changed, 76 insertions, 0 deletions
diff --git a/frontend/ast.ml b/frontend/ast.ml
new file mode 100644
index 0000000..180608c
--- /dev/null
+++ b/frontend/ast.ml
@@ -0,0 +1,76 @@
+open Lexing
+
+type position = Lexing.position
+let position_unknown = Lexing.dummy_pos
+
+type extent = position * position
+let extent_unknown = (position_unknown, position_unknown)
+
+type 'a ext = 'a * extent
+
+type id = string
+
+type typ =
+    | AST_TINT
+    | AST_TBOOL
+    | AST_TREAL
+
+type unary_op =
+    | AST_UPLUS
+    | AST_UMINUS
+    | AST_NOT
+    | AST_PRE
+
+type binary_op =
+    | AST_PLUS
+    | AST_MINUS
+    | AST_MUL
+    | AST_DIV
+    | AST_MOD
+
+    | AST_EQ
+    | AST_NE
+
+    | AST_LT
+    | AST_LE
+    | AST_GT
+    | AST_GE
+
+    | AST_AND
+    | AST_OR
+
+    | AST_ARROW
+
+type expr =
+    | AST_unary of unary_op * (expr ext)
+    | AST_binary of binary_op * (expr ext) * (expr ext)
+    | AST_identifier of id ext
+    | AST_int_const of string ext
+    | AST_bool_const of bool
+    | AST_real_const of string ext
+    | AST_if of (expr ext) * (expr ext) * (expr ext)
+    | AST_instance of (id ext) * (expr ext list)
+
+type lvalue = id
+
+type eqn =
+    | AST_assign of (lvalue ext) * (expr ext)
+    | AST_guarantee of (id ext) * (expr ext)
+    | AST_assume of (id ext) * (expr ext)
+    (* and more : automaton, activate... *)
+
+type node_decl = {
+    name : id;
+    args : (bool * (id ext) * typ) list;
+    ret : (bool * (id ext) * typ) list;
+    var : (bool * (id ext) * typ) list;
+    body : eqn ext list;
+}
+
+type const_decl = (id ext) * typ * (expr ext)
+
+type toplevel =
+    | AST_node_decl of node_decl ext
+    | AST_const_decl of const_decl ext
+
+type prog = toplevel list