From 40ea76e2310ef826aad64970eee9851f0917b830 Mon Sep 17 00:00:00 2001
From: Jan Nieuwenhuizen <janneke@gnu.org>
Date: Fri, 15 Nov 2019 09:12:08 +0100
Subject: [PATCH] HACK: flat-variable.

---
 include/mes/builtins.h |  1 +
 src/builtins.c         |  1 +
 src/variable.c         | 10 ++++++++++
 3 files changed, 12 insertions(+)

diff --git a/include/mes/builtins.h b/include/mes/builtins.h
index 08b4d844..47ff1eee 100644
--- a/include/mes/builtins.h
+++ b/include/mes/builtins.h
@@ -172,6 +172,7 @@ struct scm *struct_ref (struct scm *x, struct scm *i);
 struct scm *struct_set_x (struct scm *x, struct scm *i, struct scm *e);
 /* src/variable.c */
 struct scm *variable_ref (struct scm *var);
+struct scm *flat_variable_ref (struct scm *var);
 struct scm *variable_set_x (struct scm *var, struct scm *value);
 struct scm *variable_bound_p (struct scm *var);
 struct scm *lookup_variable (struct scm *name, struct scm *define_p);
diff --git a/src/builtins.c b/src/builtins.c
index d9e5abad..0f11d3a5 100644
--- a/src/builtins.c
+++ b/src/builtins.c
@@ -282,6 +282,7 @@ mes_builtins (struct scm *a)            /*:((internal)) */
   a = init_builtin (builtin_type, "struct-set!", 3, &struct_set_x, a);
   /* src/variable.c */
   a = init_builtin (builtin_type, "variable-ref", 1, &variable_ref, a);
+  a = init_builtin (builtin_type, "flat-variable-ref", 1, &flat_variable_ref, a);
   a = init_builtin (builtin_type, "variable-set!", 2, &variable_set_x, a);
   a = init_builtin (builtin_type, "variable-bound?", 1, &variable_bound_p, a);
   a = init_builtin (builtin_type, "lookup-variable", 2, &lookup_variable, a);
diff --git a/src/variable.c b/src/variable.c
index 384d403f..a7a2a272 100644
--- a/src/variable.c
+++ b/src/variable.c
@@ -32,6 +32,16 @@ variable_ref (struct scm *var)
   return value;
 }
 
+struct scm *
+flat_variable_ref (struct scm *var)
+{
+  assert_variable (1, var);
+  struct scm *value = var->variable;
+  if (value == cell_undefined)
+    error (cell_symbol_unbound_variable, var);
+  return value;
+}
+
 struct scm *
 variable_set_x (struct scm *var, struct scm *value)
 {