diff --git a/src/env.c b/src/env.c
index 7ccb3b8..104fd07 100644
--- a/src/env.c
+++ b/src/env.c
@@ -19,12 +19,15 @@ Object fetchFromEnvironment(const char *name, struct Environment *env)
         return errorObject(EMPTY_ENV);
 
     printd("Fetching '%s' from env\n", name);
-    // printEnv(env);
     for(int i = 0; i < env->size; i++) {
-        printd("Try %d\n", i);
-        if(env->strings[i] == NULL)
+        if(env->strings[i] == NULL) {
+            printd("Try %d (NULL)\n", i);
             break;
+        }
+        printd("Try %d (%s)\n", i, env->strings[i]);
+        debugObj(&env->objects[i]);
         if(strcmp(name, env->strings[i]) == 0) {
+            printd("Returning!\n");
             return env->objects[i];
         }
     }
@@ -58,7 +61,7 @@ struct Environment envForLambda(const Object *params, const Object *arg_forms,
 
     const Object *march = arg_forms;
     for(int i = 0; i < paramCount; i++) {
-        const char *newObjName = itemAt(params, i)->name;
+        const char *newObjName = itemAt(params, i)->string;
         const Object newEnvObj = eval(march, outer);
         addToEnv(&env, newObjName, newEnvObj); // Could use eval_forms?
         march = march->forward;
@@ -76,16 +79,12 @@ void addToEnv(struct Environment *env, const char *name, const Object obj)
         if(env->strings[i] == NULL) {
             env->strings[i] = calloc(sizeof(char), strlen(name) + 1);
             strncpy(env->strings[i], name, strlen(name));
-            env->objects[i] = obj;
-            // if(obj.type == TYPE_LIST)
-            //     copyList(&env->objects[i], &obj);
+            env->objects[i] = cloneObject(obj);
             return;
         }
         if(strcmp(env->strings[i], name) == 0) {
             cleanObject(&env->objects[i]);
-            env->objects[i] = obj;
-            // if(obj.type == TYPE_LIST)
-            //     copyList(&env->objects[i], &obj);
+            env->objects[i] = cloneObject(obj);
             return;
         }
     }
@@ -102,7 +101,7 @@ void addToEnv(struct Environment *env, const char *name, const Object obj)
 
     env->strings[i] = malloc(strlen(name) + 1);
     strncpy(env->strings[i], name, strlen(name) + 1);
-    env->objects[i] = obj;
+    env->objects[i] = cloneObject(obj);
 }
 
 void printEnv(struct Environment *env)
@@ -152,7 +151,7 @@ const char *codes[] = {
     "))",
 
     // Square a
-    "(def sq (fn (a) (exp a 2)))",
+    "(def sq (fn (a) (* a a)))",
 
     // Cube a
     "(def cube (fn (a) (exp a 3)))",
@@ -168,7 +167,7 @@ const char *codes[] = {
 
     // A demo tip calculator
     "(def spent (fn (a) \
-      (cat \"Tip: $\" \"\" \"\" (/ a 5) \".\" \
+      (cat \"Tip: $\" (/ a 5) \".\" \
         (/ (* 100 (% a 5)) 5) \
       ) \
      ))",
@@ -194,6 +193,7 @@ struct Environment defaultEnv()
     addFunc("<", &lth, &e);
     addFunc("len", &len, &e);
     addFunc("cat", &catObjects, &e);
+    addFunc("fil", &filter, &e);
 
     int i = 0;
     while(codes[i]) {
diff --git a/src/object.c b/src/object.c
index f737dd3..6be4b04 100644
--- a/src/object.c
+++ b/src/object.c
@@ -95,7 +95,7 @@ inline int isEmpty(const Object *obj)
         case TYPE_LAMBDA:
             return obj->lambda == NULL;
         case TYPE_SYMBOL:
-            return obj->name[0] == '\0';
+            return obj->string == NULL;
         case TYPE_FUNC:
             return obj->func == NULL;
         case TYPE_ERROR:
@@ -251,11 +251,9 @@ char* stringObj(char *dest, const Object *obj)
 
     if(t == TYPE_NUMBER) {
         snprintf(dest, RESULT_LENGTH, "%d", obj->number);
-    } else if(t == TYPE_SYMBOL) {
-        snprintf(dest, RESULT_LENGTH, "%s", obj->name);
     } else if(t == TYPE_BOOL) {
         snprintf(dest, RESULT_LENGTH, "%s", obj->number ? "T" : "F");
-    } else if(t == TYPE_STRING) {
+    } else if(t == TYPE_STRING || t == TYPE_SYMBOL) {
         snprintf(dest, RESULT_LENGTH, "%s", obj->string);
     } else if(t == TYPE_LIST) {
         stringList(dest, obj);
@@ -358,11 +356,12 @@ void printList(const Object *list)
  */
 void cleanObject(Object *target)
 {
+    //printf("CLEANING:");
     if(target == NULL)
         return;
 
     const Type t = target->type;
-    if(t == TYPE_STRING) {
+    if(t == TYPE_STRING || t == TYPE_SYMBOL) {
         free(target->string);
         target->string = NULL;
     } else if(t == TYPE_LIST) {
@@ -430,9 +429,8 @@ void _copyList(Object *dest, const Object *src, int delete)
             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 if (isStringy(*POINTER)) {
+            nf_addToList(dest, cloneString(*POINTER));
         } else {
             nf_addToList(dest, *POINTER);
         }
@@ -495,6 +493,28 @@ inline Object startList(const Object start)
     return list;
 }
 
+inline int isStringy(const Object src)
+{
+    return src.type == TYPE_STRING || src.type == TYPE_SYMBOL;
+}
+
+/**
+ * Clones the given lambda with new allocations
+ * Will behave unexpectedly if given something other than a lambda object!
+ */
+inline Object cloneLambda(const Object old)
+{
+    return constructLambda(&old.lambda->params, &old.lambda->body);
+}
+
+Object cloneString(Object obj)
+{
+    const char* string = obj.string;
+    obj.string = malloc(sizeof(char) * (strlen(string) + 1));
+    strcpy(obj.string, string);
+    return obj;
+}
+
 // Returns an Object with a deep copy of the given Object
 inline Object cloneList(const Object src)
 {
@@ -505,7 +525,10 @@ inline Object cloneList(const Object src)
 
 inline Object cloneObject(const Object src)
 {
-    return src.type == TYPE_LIST? cloneList(src) : src;
+    return src.type == TYPE_LIST? cloneList(src) :
+           src.type == TYPE_LAMBDA? cloneLambda(src) :
+           isStringy(src)? cloneString(src) : 
+           src;
 }
 
 inline Object numberObject(int num)
@@ -518,44 +541,25 @@ inline Object numberObject(int num)
 inline Object boolObject(int b)
 {
     Object o = newObject(TYPE_BOOL);
-    o.number = b;
+    o.number = !!b;
     return o;
 }
 
-inline Object symbolObject()
-{
-    return newObject(TYPE_SYMBOL);
-}
-
-inline Object lambdaObject()
-{
-    Object o = newObject(TYPE_LAMBDA);
-    o.lambda = malloc(sizeof(struct Lambda));
-    return o;
-}
-
-// Skips first char! Assumed to be '"'
+// Skips first and last chars! Assumed to be '"'
 inline Object objFromSlice(const char *string, int len)
 {
-    Object o = newObject(TYPE_STRING);
-    o.string = calloc(sizeof(char), len);
-    for(int i = 0; i < len - 1; i++) {
-        o.string[i] = string[i + 1];
-    }
-    o.string[len - 1] = '\0';
+    Object o = symFromSlice(&string[1], len - 1);
+    o.type = TYPE_STRING;
     return o;
 }
 
-// inline Object objFromString(const char *string)
-// {
-//     Object o = newObject(TYPE_STRING);
-//     o.string = calloc(strlen(string) + 1);
-//     for(int i = 0; i < len - 1; i++) {
-//         o.string[i] = string[i];
-//     }
-//     o.string[len - 1] = '\0';
-//     return o;
-// }
+inline Object symFromSlice(const char *string, int len)
+{
+    Object o = newObject(TYPE_SYMBOL);
+    o.string = calloc(sizeof(char), len + 1);
+    strncpy(o.string, string, len);
+    return o;
+}
 
 inline Object constructLambda(const Object *params, const Object *body)
 {
@@ -565,7 +569,8 @@ inline Object constructLambda(const Object *params, const Object *body)
     if(params->type != TYPE_LIST || body->type != TYPE_LIST)
         return errorObject(LAMBDA_ARGS_NOT_LIST);
 
-    Object o = lambdaObject();
+    Object o = newObject(TYPE_LAMBDA);
+    o.lambda = malloc(sizeof(struct Lambda));
     o.lambda->params = listObject();
     o.lambda->body = listObject();
     copyList(&o.lambda->params, params);
@@ -580,16 +585,9 @@ 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)
         return boolObject(0);
+    return boolObject(1);
 }
diff --git a/src/object.h b/src/object.h
index dcb9737..90740da 100644
--- a/src/object.h
+++ b/src/object.h
@@ -1,9 +1,8 @@
 #ifndef OBJECT_H
 #define OBJECT_H
 
-#define MAX_TOK_LEN 10  // 11
 #define MAX_TOK_CNT 128 // 128
-#define MAX_ENV_ELM 25  // 50
+#define MAX_ENV_ELM 50  // 50
 
 #define FOR_POINTER_IN_LIST(_list) \
     for(Object *_element = _list->list; \
@@ -36,7 +35,8 @@ enum errorCode {
     UNEXPECTED_FORM,
     LISTS_NOT_SAME_SIZE,
     SYMBOLS_CANT_START_WITH_DIGITS,
-    UNSUPPORTED_NUMBER_TYPE
+    UNSUPPORTED_NUMBER_TYPE,
+    NOT_A_SYMBOL
 };
 
 //#ifdef STANDALONE
@@ -56,7 +56,8 @@ static const char *errorText[] = {
     "UNEXPECTED_FORM",
     "LISTS_NOT_SAME_SIZE",
     "SYMBOLS_CANT_START_WITH_DIGITS",
-    "UNSUPPORTED_NUMBER_TYPE"
+    "UNSUPPORTED_NUMBER_TYPE",
+    "NOT_A_SYMBOL"
 };
 //#endif
 
@@ -84,7 +85,6 @@ struct Object {
     union {
         int number;
         Object *list;
-        char name[MAX_TOK_LEN];
         char *string;
         Object (*func)(Object, Object, struct Environment *);
         struct Lambda *lambda; // Maybe better as not a pointer?
@@ -121,20 +121,25 @@ void printAndClean(Object *target);
 void allocObject(Object **spot, const Object src);
 void appendList(Object *dest, const Object *src);
 
+int isStringy(const Object src);
+
+Object cloneList(const Object src);
+Object cloneString(Object obj);
+Object cloneLambda(const Object old);
+Object cloneObject(const Object src);
+
 Object newObject(Type type);
 Object listObject();
 Object startList(const Object start);
-Object cloneList(const Object src);
-Object cloneObject(const Object src);
 Object lambdaObject();
 Object symbolObject();
 Object objFromSlice(const char *string, int len);
+Object symFromSlice(const char *string, int len);
 Object boolObject(int b);
 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 b9a6870..fd4128d 100644
--- a/src/pebblisp.c
+++ b/src/pebblisp.c
@@ -12,13 +12,14 @@
 Object evalDefArgs(const Object *argForms, struct Environment *env)
 {
     const Object *newSymbol = argForms;
-    const char *name = newSymbol->name;
+    const char *name = newSymbol->string;
 
-    const Object newValue = eval(newSymbol->forward, env);
+    Object newValue = eval(newSymbol->forward, env);
 
     addToEnv(env, name, newValue);
+    cleanObject(&newValue);
 
-    return *newSymbol;
+    return cloneObject(*newSymbol);
 }
 
 Object evalIfArgs(const Object *argForms, struct Environment *env)
@@ -67,13 +68,16 @@ Object evalMapArgs(const Object *argForms, struct Environment *env)
 Object evalBuiltIns(const Object *first, const Object *rest,
                     struct Environment *env)
 {
-    if(strcmp(first->name, "def") == 0) {
+    if(first->type != TYPE_SYMBOL) {
+        return errorObject(NOT_A_SYMBOL);
+    }
+    if(strcmp(first->string, "def") == 0) {
         return evalDefArgs(rest, env);
-    } else if(strcmp(first->name, "if") == 0) {
+    } else if(strcmp(first->string, "if") == 0) {
         return evalIfArgs(rest, env);
-    } else if(strcmp(first->name, "fn") == 0) {
+    } else if(strcmp(first->string, "fn") == 0) {
         return evalLambdaArgs(rest);
-    } else if(strcmp(first->name, "map") == 0) {
+    } else if(strcmp(first->string, "map") == 0) {
         return evalMapArgs(rest, env);
     }
 
@@ -91,18 +95,14 @@ void eval_forms(Object *destList, const Object *src, struct Environment *env)
 
 Object eval(const Object *obj, struct Environment *env)
 {
-    // printf("eval():\n");
-    // printObj(obj);
     switch(obj->type) {
         case TYPE_NUMBER:
         case TYPE_BOOL:
-            return *obj; // Return as is
-
         case TYPE_STRING:
-            return copyString(*obj);
+            return cloneObject(*obj);
 
         case TYPE_SYMBOL:
-            return fetchFromEnvironment(obj->name, env);
+            return fetchFromEnvironment(obj->string, env);
 
         case TYPE_LIST:
         {
@@ -138,6 +138,10 @@ Object eval(const Object *obj, struct Environment *env)
                     cleanObject(&rest[i]);
                 }
 
+                // Consider the object a partial function
+                if(length == 1)
+                    return cloneObject(*obj);
+
                 return func_eval;
 
             } else if (first_eval.type == TYPE_LAMBDA) {
@@ -155,6 +159,7 @@ Object eval(const Object *obj, struct Environment *env)
                 return list;
             }
         }
+
         case TYPE_LAMBDA:
             return errorObject(UNEXPECTED_FORM);
 
@@ -213,6 +218,8 @@ Object _basicOp(const Object *obj1, const Object *obj2, const char op,
             return numberObject(n1 % n2);
 
         case '=':
+            if(obj1->type == TYPE_STRING || obj2->type == TYPE_STRING)
+                return boolObject(!strcmp(obj1->string, obj2->string));
             return boolObject(n1 == n2);
         case '>':
             return boolObject(n1 > n2);
@@ -271,6 +278,21 @@ BASIC_OP(lth, '<');
 
 #undef BASIC_OP
 
+Object filter(Object obj1, Object obj2, struct Environment *env)
+{
+    Object filteredList = listObject();
+    Object *filteringList = &obj2;
+    FOR_POINTER_IN_LIST(filteringList) {
+        Object conditional = cloneObject(obj1);
+        nf_addToList(&conditional, *POINTER); // cloneObject()?
+        conditional = eval(&conditional, env);
+        if(conditional.number == 1) {
+            nf_addToList(&filteredList, *POINTER);
+        }
+    }
+    return filteredList;
+}
+
 void copySlice(char * dest, struct Slice *src)
 {
     if(!dest || !src)
@@ -321,22 +343,23 @@ Result readSeq(struct Slice *tokens)
             return result(res, rest);
         }
         Result r = parse(tokens);
-        nf_addToList(&res, r.obj);
+        nf_addToList(&res, cloneObject(r.obj));
         tokens = r.slices;
+        cleanObject(&r.obj);
     }
 }
 
 Object parseDecimal(struct Slice *s)
 {
-        int num = 0;
-        for(int i = 0; i < s->length; i++) {
-            if(!isDigit(s->text[i])) {
-                return errorObject(SYMBOLS_CANT_START_WITH_DIGITS);
-            }
-            num *= 10;
-            num += s->text[i] - '0';
+    int num = 0;
+    for(int i = 0; i < s->length; i++) {
+        if(!isDigit(s->text[i])) {
+            return errorObject(SYMBOLS_CANT_START_WITH_DIGITS);
         }
-        return numberObject(num);
+        num *= 10;
+        num += s->text[i] - '0';
+    }
+    return numberObject(num);
 }
 
 Object parseAtom(struct Slice *s)
@@ -357,9 +380,7 @@ Object parseAtom(struct Slice *s)
     } else if (s->text[0] == '"') {
         return objFromSlice(s->text, s->length);
     } else {
-        Object o = symbolObject();
-        copySlice(o.name, s);
-        return o;
+        return symFromSlice(s->text, s->length);
     }
 }
 
@@ -368,9 +389,12 @@ Object parseEval(const char *input, struct Environment *env)
     struct Slice *tokens = nf_tokenize(input);
     if(!tokens)
         return errorObject(MISMATCHED_PARENS);
+    if(!tokens->text)
+        return symFromSlice(" ", 1);
 
-#ifdef DEBUG
+    #ifdef DEBUG
     struct Slice *debug = tokens;
+    printd("start slice\n");
     if(debug) {
         while(debug->text) {
             char tok[MAX_TOK_LEN];
@@ -379,7 +403,7 @@ Object parseEval(const char *input, struct Environment *env)
             debug++;
         }
     }
-#endif
+    #endif
 
     int i = 0;
     int parens = 0;
@@ -400,6 +424,7 @@ Object parseEval(const char *input, struct Environment *env)
                     Object parsed = parse(tok).obj;
                     tok = &tok[i + 1];
                     i = -1;
+                    //printObj(&parsed);
                     obj = eval(&parsed, env);
                     cleanObject(&parsed);
                 }
diff --git a/src/pebblisp.h b/src/pebblisp.h
index 4bfa11e..294c06b 100644
--- a/src/pebblisp.h
+++ b/src/pebblisp.h
@@ -35,14 +35,6 @@ void eval_forms(Object *destList, const Object *src, struct Environment *env);
 
 Object evalLambdaArgs(const Object *arg_forms);
 
-struct Environment defaultEnv();
-void deleteEnv(struct Environment *e);
-void addToEnv(struct Environment *env, const char *name, const Object obj);
-Object fetchFromEnvironment(const char *name, struct Environment *env);
-void printEnv(struct Environment *env);
-struct Environment envForLambda(const Object *params, const Object *arg_forms,
-                                struct Environment *outer);
-
 Result result(Object obj, struct Slice *slices);
 
 // Slices
@@ -57,5 +49,6 @@ BASIC_OP(mod); BASIC_OP(equ);
 BASIC_OP(gth); BASIC_OP(lth);
 #undef BASIC_OP
 Object catObjects(const Object obj1, const Object obj2, struct Environment *env);
+Object filter(Object obj1, Object obj2, struct Environment *env);
 
 #endif
diff --git a/src/tests.sh b/src/tests.sh
index 7871e87..2b9d127 100755
--- a/src/tests.sh
+++ b/src/tests.sh
@@ -13,7 +13,7 @@ pass() {
 }
 
 fail() {
-        echo "$1 test FAILED"
+        echo "$1 test FAILED $2"
         ((FAILS++))
 }
 
@@ -28,7 +28,7 @@ check() {
         if [ "$output" == "$3" ]; then
                 pass $1
         else
-                fail $1
+                fail $1 "$2"
                 echo "  Expected '$3' but received '$output'"
         fi
 }
@@ -51,11 +51,13 @@ echo ""
 check "GratrThn" "(> 23847123 19375933)" "T"
 check "LessThan" "(< 23847123 19375933)" "F"
 check "Equality" "(= 987654321 987654321 )" "T"
+check "StringEquality" "(= \"Bean\" \"Bean\" )" "T"
+check "Stringinequality" "(= \"Beans\" \"Bean\" )" "F"
 echo ""
 check "IfReturn" "(if (T) 123456789 987654321)" "123456789"
 check "IfRetTwo" "(if F 123456789 987654321)" "987654321"
 check "EmptyCnd" "(if () T F)" "F"
-# check "EtyLstLt" "(if (()) T F)" "T"
+check "EtyLstLt" "(if (()) T F)" "T"
 echo ""
 check "RegLists" "(1 2 3 4 5)" "( 1 2 3 4 5 )"
 check "MultiTypeList" "(10 20 \"rascals\")" "( 10 20 rascals )"
@@ -68,28 +70,39 @@ check "VWidwSpc" "       (     +     1093      102852       )       " "103945"
 echo ""
 check "DemoFunc" "(spent 68)" "Tip: \$13.60"
 echo ""
-check "MultStmt" "(def yee (fn (a) (* 10 a))) (yee 5)" "50"
-check "DefinMap" "(def yee (fn (a) (* 10 a))) (map yee (5 10 2 (+ 12 0)))" "( 50 100 20 120 )"
+check "MultStmt" "(def yee (fn (a) (* 10 a))) ; (yee 5)" "50"
+check "DefinMap" "(def yee (fn (a) (* 10 a))) ; (map yee (5 10 2 (+ 12 0)))" "( 50 100 20 120 )"
 check "FbnciSeq" "(def fib (fn (a) \
                     (if (< a 2) \
                       a \
                       (+ (fib (- a 1)) (fib (- a 2))) \
-                  ))) \
+                  )));\
                   (fib 20)" "6765"
+check "Factorial" "(def fac (fn (a) \
+                     (if (= a 1) \
+                       1 \
+                       (* a (fac (- a 1)) ) \
+                   )));\
+                   (fac 11)" "39916800"
 echo ""
 check "ExplicitCat" "(cat \"Big\" \" Kitty\")" "Big Kitty"
 check "CatNums" "(cat \"There are \" (+ 2 3) \" kitties\")" "There are 5 kitties"
 check "ImplicitCat" "(+ \"There are \" (* 5 4) \" bonks\")" "There are 20 bonks"
-# Not recommended
+# Mixing of `+` and implicit cat not recommended:
 check "CatAssocLeft" "(+ 10 20 \" rascals\")" "30 rascals"
 echo ""
+check "LambdaClone" "(def y (fn (a) (* 10 a))) (def b y) (def y 12345) ((b 5) y)" "( 50 12345 )"
+echo ""
 check "EvalElems" "((* 10 10) 7)" "( 100 7 )"
-check "Duplicate" "(def dupe (fn (a) (a a a))) (dupe (*10 10))" "( 100 100 100 )"
+check "Duplicate" "(def dupe (fn (a) (a a a)));(dupe (*10 10))" "( 100 100 100 )"
 echo ""
 check "Squaring" "(sq 9876)" "97535376"
 check "Cubing" "(cube 81)" "531441"
 check "Exponent" "(exp 9 9)" "387420489"
 echo ""
+check "Filtering" "(fil (< 321) (30 300 90 1200 135 801))" "( 1200 801 )"
+check "MapFilter" "(fil (< 50) (map sq (1 2 3 4 5 6 7 8 9 10 11 12)))" "( 64 81 100 121 144 )"
+echo ""
 
 if [ "$FAILS" -ne "0" ]; then
         echo "$FAILS Tests Failed"