fixed issue #22

Author: TheRealMichaelWang

src/io.cpp

@@ -185,5 +185,16 @@ namespace fastcode {
 
 			return gc->new_apartment(new value(VALUE_TYPE_NUMERICAL, new long double(1)));
 		}
+
+		runtime::reference_apartment* system_call(std::list<value*> args, runtime::garbage_collector* gc) {
+			match_arg_len(args, 1);
+			match_arg_type(args.front(), VALUE_TYPE_COLLECTION);
+
+			char* command = to_c_str(args.front());
+			system(command);
+			delete[] command;
+
+			return gc->new_apartment(new value(VALUE_TYPE_NULL, nullptr));
+		}
 	}
 }

src/io.h

@@ -16,6 +16,8 @@ namespace fastcode {
 
 		runtime::reference_apartment* file_read_text(std::list<value*> args, runtime::garbage_collector* gc);
 		runtime::reference_apartment* file_write_text(std::list<value*> args, runtime::garbage_collector* gc);
+
+		runtime::reference_apartment* system_call(std::list<value*> args, runtime::garbage_collector* gc);
 	}
 	void handle_syntax_err(int syntax_error, unsigned int pos, const char* source);
 	void handle_runtime_err(int runtime_error, parsing::token* err_tok);

src/references.cpp

@@ -53,7 +53,7 @@ namespace fastcode {
 		}
 
 		void reference_apartment::remove_reference(reference_apartment* parent) {
-			if (this->references == 0)
+			if (this->references - parent->references < 0)
 				throw ERROR_CANNOT_DEREFERENCE;
 			this->references -= parent->references;
 			unsigned int children_count = 0;

src/runtime.cpp

@@ -44,6 +44,7 @@ namespace fastcode {
 			import_func("len", builtins::get_length);
 			import_func("range", builtins::get_range);
 			import_func("handle", builtins::get_handle);
+			import_func("system", builtins::system_call);
 			import_func("read@file", builtins::file_read_text);
 			import_func("write@file", builtins::file_write_text);
 			import_func("count@linq", builtins::count_instances);
@@ -332,7 +333,7 @@ namespace fastcode {
 								call_stack.top()->manager->declare_var(set_tok->destination->get_identifier(), eval->get_value());
 							}
 						}
-					}
+					}          
 				}
 				else {
 					if (eval->type == VALUE_EVAL_TYPE_REF) {

src/variables.cpp

@@ -48,7 +48,8 @@ namespace fastcode {
 			if (parent == nullptr)
 				hash_buckets[id_hash % VARIABLE_HASH_BUCKET_SIZE] = new variable_bucket(id_hash, reference);
 			else
-				parent = new variable_bucket(id_hash, reference);
+				parent->next_bucket = new variable_bucket(id_hash, reference);
+			size++;
 			return reference;
 		}
 
@@ -71,6 +72,7 @@ namespace fastcode {
 				parent->next_bucket = bucket->next_bucket;
 			bucket->apartment->remove_reference();
 			delete bucket;
+			size--;
 		}
 
 		bool variable_manager::has_var(unsigned long id_hash)