From 6be79eda61b3c64b38528c023845991a0cb4a274 Mon Sep 17 00:00:00 2001
From: Clyne Sullivan <clyne@bitgloo.com>
Date: Sat, 15 Jun 2024 21:06:27 -0400
Subject: recursion; list via support.c

---
 support.c | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

(limited to 'support.c')

diff --git a/support.c b/support.c
index cc0304f..44a39e4 100644
--- a/support.c
+++ b/support.c
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <stdint.h>
+#include <stdlib.h>
 
 extern int32_t sp;
 extern int32_t stack;
@@ -9,6 +10,11 @@ void emit()
     putchar(*(&stack + --sp));
 }
 
+void print()
+{
+    printf("%d\n", *(&stack + --sp));
+}
+
 void sub()
 {
     int32_t *st = &stack;
@@ -33,3 +39,33 @@ void eq()
     --sp;
     st[sp - 1] = st[sp - 1] == st[sp];
 }
+
+void cons()
+{
+    int32_t *st = &stack;
+    int32_t *pair = malloc(2 * sizeof(int32_t));
+    --sp;
+    pair[0] = st[sp];
+    pair[1] = st[sp - 1];
+    st[sp - 1] = (int32_t)pair;
+}
+
+void car()
+{
+    int32_t *st = &stack;
+    st[sp - 1] = ((int32_t *)st[sp - 1])[0];
+}
+
+void cdr()
+{
+    int32_t *st = &stack;
+    st[sp - 1] = ((int32_t *)st[sp - 1])[1];
+}
+
+void decons()
+{
+    int32_t *st = &stack;
+    --sp;
+    free((int32_t *)st[sp]);
+}
+
-- 
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