From 894dc6b6d2d466a9b37d7f40df34c6d980fc693e Mon Sep 17 00:00:00 2001
From: Justin Ethier <justin.ethier@gmail.com>
Date: Tue, 11 Aug 2015 22:26:20 -0400
Subject: [PATCH] Experimenting with a macro type

---
 include/cyclone/types.h |  4 ++++
 runtime.c               | 16 +++++++++++++++-
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/include/cyclone/types.h b/include/cyclone/types.h
index 434b275c..def678e9 100644
--- a/include/cyclone/types.h
+++ b/include/cyclone/types.h
@@ -75,6 +75,7 @@ typedef long tag_type;
 #define boolean_tag 15
 #define cvar_tag 16
 #define vector_tag 17
+#define macro_tag 18
 
 #define nil NULL
 #define eq(x,y) (x == y)
@@ -212,6 +213,7 @@ cons_type n; n.tag = cons_tag; n.cons_car = a; n.cons_cdr = d;
 
 /* Closure types */
 
+typedef struct {tag_type tag; function_type fn; int num_args; } macro_type;
 typedef struct {tag_type tag; function_type fn; int num_args; } closure0_type;
 typedef struct {tag_type tag; function_type fn; int num_args; object elt1;} closure1_type;
 typedef struct {tag_type tag; function_type fn; int num_args; object elt1,elt2;} closure2_type;
@@ -226,7 +228,9 @@ typedef closure3_type *closure3;
 typedef closure4_type *closure4;
 typedef closureN_type *closureN;
 typedef closure0_type *closure;
+typedef closure0_type *macro;
 
+#define mmacro(c,f) macro_type c; c.tag = macro_tag; c.fn = f; c.num_args = -1;
 #define mclosure0(c,f) closure0_type c; c.tag = closure0_tag; c.fn = f; c.num_args = -1;
 #define mclosure1(c,f,a) closure1_type c; c.tag = closure1_tag; \
    c.fn = f; c.num_args = -1; c.elt1 = a;
diff --git a/runtime.c b/runtime.c
index 56b80064..f61a0e45 100644
--- a/runtime.c
+++ b/runtime.c
@@ -418,7 +418,8 @@ object Cyc_display(object x, FILE *port)
  if (nullp(x)) {fprintf(port, "()"); return quote_void;}
  if (obj_is_char(x)) {fprintf(port, "%c", obj_obj2char(x)); return quote_void;}
  switch (type_of(x))
-   {case closure0_tag:
+   {case macro_tag:
+    case closure0_tag:
     case closure1_tag:
     case closure2_tag:
     case closure3_tag:
@@ -1852,6 +1853,7 @@ object apply(object cont, object func, object args){
       // TODO: should probably check arg counts and error out if needed
       ((primitive_type *)func)->fn(cont, args);
       break;
+    case macro_tag:
     case closure0_tag:
     case closure1_tag:
     case closure2_tag:
@@ -1962,6 +1964,13 @@ char *transport(x, gcgen) char *x; int gcgen;
        forward(x) = nx; type_of(x) = forward_tag;
        allocp = ((char *) nx)+sizeof(cons_type);
        return (char *) nx;}
+    case macro_tag:
+      {register macro nx = (macro) allocp;
+       type_of(nx) = macro_tag; nx->fn = ((macro) x)->fn;
+       nx->num_args = ((macro) x)->num_args;
+       forward(x) = nx; type_of(x) = forward_tag;
+       allocp = ((char *) nx)+sizeof(macro_type);
+       return (char *) nx;}
     case closure0_tag:
       {register closure0 nx = (closure0) allocp;
        type_of(nx) = closure0_tag; nx->fn = ((closure0) x)->fn;
@@ -2200,6 +2209,11 @@ void GC_loop(int major, closure cont, object *ans, int num_ans)
 #endif
         transp(car(scanp)); transp(cdr(scanp));
         scanp += sizeof(cons_type); break;
+      case macro_tag:
+#if DEBUG_GC
+ printf("DEBUG transport macro \n");
+#endif
+        scanp += sizeof(macro_type); break;
       case closure0_tag:
 #if DEBUG_GC
  printf("DEBUG transport closure0 \n");