From 1ac5b6458c54a7a7fd7773c714b6cdd22c9a4894 Mon Sep 17 00:00:00 2001
From: Yuichi Nishiwaki <yuichi.nishiwaki@gmail.com>
Date: Sat, 7 Dec 2013 07:04:26 -0800
Subject: [PATCH] add pic_null_syntactic_env and pic_minimal_syntactic_env

---
 include/picrin/macro.h |  2 ++
 src/macro.c            | 24 +++++++++++++++++++++++-
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/include/picrin/macro.h b/include/picrin/macro.h
index ef51c85c..0a01e00d 100644
--- a/include/picrin/macro.h
+++ b/include/picrin/macro.h
@@ -46,6 +46,8 @@ struct pic_sc {
 #define pic_senv(v) ((struct pic_senv *)pic_ptr(v))
 #define pic_senv_p(v) (pic_type(v) == PIC_TT_SENV)
 
+struct pic_senv *pic_null_syntactic_env(pic_state *pic);
+struct pic_senv *pic_minimal_syntactic_env(pic_state *pic);
 struct pic_senv *pic_core_syntactic_env(pic_state *pic);
 
 struct pic_syntax *pic_syntax_new(pic_state *, int kind, pic_sym sym);
diff --git a/src/macro.c b/src/macro.c
index b64a263f..7dddcf60 100644
--- a/src/macro.c
+++ b/src/macro.c
@@ -31,7 +31,7 @@ new_uniq_sym(pic_state *pic, pic_sym base)
 }
 
 struct pic_senv *
-pic_core_syntactic_env(pic_state *pic)
+pic_null_syntactic_env(pic_state *pic)
 {
   struct pic_senv *senv;
 
@@ -42,12 +42,32 @@ pic_core_syntactic_env(pic_state *pic)
   senv->xlen = 0;
   senv->xcapa = PIC_MACROS_SIZE;
 
+  return senv;
+}
+
 #define register_core_syntax(pic,senv,kind,name) do {			\
     senv->stx[senv->xlen] = pic_syntax_new(pic, kind, pic_intern_cstr(pic, name)); \
     xh_put(senv->tbl, name, ~senv->xlen);				\
     senv->xlen++;							\
   } while (0)
 
+struct pic_senv *
+pic_minimal_syntactic_env(pic_state *pic)
+{
+  struct pic_senv *senv = pic_null_syntactic_env(pic);
+
+  register_core_syntax(pic, senv, PIC_STX_DEFLIBRARY, "define-library");
+  register_core_syntax(pic, senv, PIC_STX_IMPORT, "import");
+  register_core_syntax(pic, senv, PIC_STX_EXPORT, "export");
+
+  return senv;
+}
+
+struct pic_senv *
+pic_core_syntactic_env(pic_state *pic)
+{
+  struct pic_senv *senv = pic_null_syntactic_env(pic);
+
   register_core_syntax(pic, senv, PIC_STX_DEFINE, "define");
   register_core_syntax(pic, senv, PIC_STX_SET, "set!");
   register_core_syntax(pic, senv, PIC_STX_QUOTE, "quote");
@@ -63,6 +83,8 @@ pic_core_syntactic_env(pic_state *pic)
   return senv;
 }
 
+#undef register_core_syntax
+
 static struct pic_senv *
 new_global_senv(pic_state *pic)
 {