From bb4e176e42f5079ee81fa682f482f37de153d154 Mon Sep 17 00:00:00 2001
From: Justin Ethier <justin.ethier@gmail.com>
Date: Thu, 16 Nov 2023 19:37:36 -0800
Subject: [PATCH] WIP, read rationals as inexact nums

---
 CHANGELOG.md |  1 +
 runtime.c    | 21 +++++++++++++--------
 2 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 64fc54c0..5be088ad 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -20,6 +20,7 @@ Features
 
 - Arthur Maciel added `make-opaque` to `(cyclone foreign)`.
 - Add `memory-streams` to the list of symbols that `(features)` can return, indicating that the current installation supports in-memory streams.
+- Enhanced the reader to load rationals as inexact numbers.
 
 Bug Fixes
 
diff --git a/runtime.c b/runtime.c
index 11fcf9db..716e8075 100644
--- a/runtime.c
+++ b/runtime.c
@@ -2617,14 +2617,20 @@ int str_is_bignum(str2int_errno errnum, char *c)
   return 1;
 }
 
-float string2rational(char *s){
+double string2rational(char *s)
 {
-  // TODO: this is terrible, needs work:
   char *nom = _strdup(s);
-  char *denom = strchr(s, '\');
+  char *denom = strchr(nom, '/');
+  if (denom == NULL) {
+    // Should never happen since we check for '/' elsewhere
+    return 0.0;
+  }
   denom[0] = '\0';
   denom++;
-  return strtol(nom, NULL, 10) / strtol(denom, NULL, 10);
+// TODO: check return values from strtol
+  double x = strtol(nom, NULL, 10);
+  double y = strtol(denom, NULL, 10);
+  return x / y;
 }
 
 object Cyc_string2number_(void *data, object cont, object str)
@@ -2640,10 +2646,9 @@ object Cyc_string2number_(void *data, object cont, object str)
     if (rv == STR2INT_SUCCESS) {
       _return_closcall1(data, cont, obj_int2obj(result));
     } else if (rv == STR2INT_RATIONAL) {
-      // TODO: function to handle this:
-      // - find / symbol
-      // - parse int on either side (could be bignums!)
-      // - for now, perform division and return float. longer-term, return rational
+      double d = string2rational(s);
+      make_double(result, d);
+      _return_closcall1(data, cont, &result);
     } else if (str_is_bignum(rv, s)) {
       alloc_bignum(data, bn);
       if (MP_OKAY != mp_read_radix(&(bignum_value(bn)), s, 10)) {