From f488e29c5434b8055fef6abbeb45062ebe463c2b Mon Sep 17 00:00:00 2001
From: = <=>
Date: Fri, 15 May 2020 21:28:16 +0100
Subject: [PATCH] Implement liberal string copying and destruction

---
 src/env.c      |  2 +-
 src/object.c   | 19 ++++++++++++++++---
 src/object.h   |  1 +
 src/pebblisp.c | 10 +++++++---
 4 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/src/env.c b/src/env.c
index 0a266f0..590f0af 100644
--- a/src/env.c
+++ b/src/env.c
@@ -165,7 +165,7 @@ struct Environment defaultEnv()
     parseEval("(def min (fn (a b) (if (< a b) a b)))", &e);
     parseEval("(def ad (fn (a) (if (> a 10) a (ad (* 10 a) ))))", &e);
     parseEval("(def spent (fn (a) \
-                (cat \"Tip: $\" (/ a 5) \".\" \
+                (cat \"Tip: $\" \"\" \"\" (/ a 5) \".\" \
                   (/ (* 100 (% a 5)) 5) \
                 ) \
                ))", &e);
diff --git a/src/object.c b/src/object.c
index 0d359ad..e29b355 100644
--- a/src/object.c
+++ b/src/object.c
@@ -319,8 +319,8 @@ void cleanObject(Object *target)
         // TODO Why does this break?
         // Probably multiple objects referencing the same string
 
-        // free(target->string);
-        // target->string = NULL;
+        free(target->string);
+        target->string = NULL;
     }
     target->forward = NULL;
 }
@@ -367,10 +367,15 @@ void _copyList(Object *dest, const Object *src, int delete)
         deleteList(dest);
 
     FOR_POINTER_IN_LIST(src) {
-        nf_addToList(dest, *POINTER);
         if(POINTER->type == TYPE_LIST) {
+            nf_addToList(dest, *POINTER);
             tail(dest)->list = NULL;
             _copyList(tail(dest), POINTER, 0);
+        } else if (POINTER->type == TYPE_STRING) {
+            Object t = copyString(*POINTER);
+            nf_addToList(dest, t);
+        } else {
+            nf_addToList(dest, *POINTER);
         }
     }
 }
@@ -486,6 +491,14 @@ inline Object errorObject(enum errorCode err)
     return o;
 }
 
+Object copyString(Object obj)
+{
+    const char* string = obj.string;
+    obj.string = malloc(sizeof(char) * (strlen(string) + 1));
+    strcpy(obj.string, string);
+    return obj;
+}
+
 inline Object toBool(const Object test)
 {
     if(test.number == 0)
diff --git a/src/object.h b/src/object.h
index cd9c5fb..2233133 100644
--- a/src/object.h
+++ b/src/object.h
@@ -126,6 +126,7 @@ Object numberObject(int num);
 Object errorObject(enum errorCode err);
 Object constructLambda(const Object *params, const Object *body);
 
+Object copyString(Object obj);
 // Object version of listLength()
 Object len(Object obj1, Object, struct Environment *);
 
diff --git a/src/pebblisp.c b/src/pebblisp.c
index 4255110..a831b1b 100644
--- a/src/pebblisp.c
+++ b/src/pebblisp.c
@@ -92,8 +92,9 @@ Object eval(const Object *obj, struct Environment *env)
     switch(obj->type) {
         case TYPE_NUMBER:
         case TYPE_BOOL:
-        case TYPE_STRING:
             return *obj; // Return as is
+        case TYPE_STRING:
+            return copyString(*obj); // Return as is
 
         case TYPE_SYMBOL:
             return fetchFromEnvironment(obj->name, env);
@@ -127,6 +128,7 @@ Object eval(const Object *obj, struct Environment *env)
                 Object func_eval = rest[0];
                 for(int i = 1; i < length; i++) {
                     func_eval = first_eval.func(func_eval, rest[i], env);
+                    cleanObject(&rest[i]);
                 }
 
                 // deleteList(obj); // Decreases indirectly lost memory, but fails on Pebble
@@ -164,13 +166,15 @@ Result result(Object obj, struct Slice *slices)
 
 Object catObjects(const Object obj1, const Object obj2, struct Environment *env)
 {
-    const Object evalObj1 = eval(&obj1, env);
-    const Object evalObj2 = eval(&obj2, env);
+    Object evalObj1 = eval(&obj1, env);
+    Object evalObj2 = eval(&obj2, env);
 
     char str1[100] = "";
     char str2[100] = "";
     stringObj(str1, &evalObj1);
     stringObj(str2, &evalObj2);
+    cleanObject(&evalObj1);
+    cleanObject(&evalObj2);
     int length = strlen(str1) + strlen(str2) + 1;
 
     Object o = newObject(TYPE_STRING);