4 files changed, 43 insertions, 4 deletions

diff --git a/src/eval.c b/src/eval.c
index dc15223..386442c 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -86,7 +86,6 @@ sym_t* try_eval_internal(sym_t* symbol, hashtable_t* symbolScope) {
 		exec_all(symbol->args, symbol->argCount - 1, symbolScope);
 		return eval(symbol->args[symbol->argCount - 1], symbolScope);
 	}
-	/* TODO: rename storel */
 	else if (hash == get_hash("store")) {
 		/* first arg is value, remaining args are names */
 		/* TODO: recursion for multiple pairs */
@@ -99,6 +98,18 @@ sym_t* try_eval_internal(sym_t* symbol, hashtable_t* symbolScope) {
 		hashtable_add_pair(symbolScope->parent, p);
 		return init_sym_int(1);
 	}
+	else if (hash == get_hash("update")) {
+		/* first arg is value, remaining args are names */
+		/* TODO: recursion for multiple pairs */
+		sym_t* v = eval(symbol->args[1], symbolScope);
+		char* k = symtos(v);
+		destroy_sym(v);
+		sym_t* value = symbol->args[0];
+		pair_t p = init_pair(k, (void*)value);
+		free(k);
+		hashtable_update_pair_recurse(symbolScope->parent, p);
+		return init_sym_int(1);
+	}
 	/* TODO: release()/free() method? */
 	else if (hash == get_hash("eq")) {
 		litType_t type = NO_TYPE;
@@ -175,6 +186,17 @@ sym_t* try_eval_internal(sym_t* symbol, hashtable_t* symbolScope) {
 		}
 		return init_sym_int(sum);
 	}
+	else if (hash == get_hash("sub")) {
+		sym_t* v1 = eval(symbol->args[0], symbolScope);
+		int sum = symtoi(v1);
+		destroy_sym(v1);
+		for (int i = 1; i < symbol->argCount; i++) {
+			sym_t* v = eval(symbol->args[i], symbolScope);
+			sum -= symtoi(v);
+			destroy_sym(v);
+		}
+		return init_sym_int(sum);
+	}
 	else if (hash == get_hash("print")) {
 		sym_t* v = eval(symbol->args[0], symbolScope);
 		if (v->litType == INT) {
diff --git a/src/hashtable.c b/src/hashtable.c
index 3a83861..2ec766d 100644
--- a/src/hashtable.c
+++ b/src/hashtable.c
@@ -49,18 +49,28 @@ unsigned int hashtable_add_pair(hashtable_t* hashtable, pair_t pair) {
 	unsigned int hash = get_hash(pair.key);
 	for (int i = 0; i < hashtable->capacity; i++) {
 		pair_t p = hashtable->pairs[hash % hashtable->capacity];
-		if (p.key == NULL || p.key == pair.key) {
+		if (p.key == NULL || strcmp(p.key, pair.key) == 0) {
 			hashtable->pairs[hash % hashtable->capacity] = pair;
 			return hash;
 		}
 	}
 	return 0;
 }
+unsigned int hashtable_update_pair_recurse(hashtable_t* origin, pair_t pair) {
+	pair_t p = hashtable_get_pair(origin, pair.key);
+	if (p.key != NULL) {
+		return hashtable_add_pair(origin, pair);
+	}
+	if (origin->parent != NULL) {
+		return hashtable_update_pair_recurse(origin->parent, pair);
+	}
+	return 0;
+}
 pair_t hashtable_get_pair(hashtable_t* hashtable, char* key) {
 	unsigned int hash = get_hash(key);
 	for (int i = 0; i < hashtable->capacity; i++) {
 		pair_t p = hashtable->pairs[hash % hashtable->capacity];
-		if (p.key == key) {
+		if (p.key != NULL && strcmp(p.key, key) == 0) {
 			return p;
 		}
 		else if (p.key == NULL) {
diff --git a/src/hashtable.h b/src/hashtable.h
index 34751fa..6f0dc51 100644
--- a/src/hashtable.h
+++ b/src/hashtable.h
@@ -16,6 +16,7 @@ hashtable_t* init_hashtable(unsigned int capacity, hashtable_t* parent);
 void destroy_hashtable(hashtable_t* hashtable);
 unsigned int get_hash(char* str);
 unsigned int hashtable_add_pair(hashtable_t* hashtable, pair_t pair);
+unsigned int hashtable_update_pair_recurse(hashtable_t* origin, pair_t pair);
 pair_t hashtable_get_pair(hashtable_t* hashtable, char* key);
 pair_t hashtable_get_pair_recurse(hashtable_t* origin, char* key);
 
diff --git a/src/parse.c b/src/parse.c
index 0144f44..79c1dc4 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -104,7 +104,13 @@ symset_t* parse_symbols(char** str) {
 				}
 				/* int */
 				else {
-					int v = atoi(symbolName);
+					int v;
+					if (symbolName[0] == '-') {
+						v = atoi(symbolName + 1) * -1;
+					}
+					else {
+						v = atoi(symbolName);
+					}
 					symbol = init_sym_int(v);
 				}
 				symset_add_symbol(symbolSet, symbol);