including iostream in common headers

Author: noah1510

common/include/acceleration.hpp

@@ -5,6 +5,8 @@
 #include "time.hpp"
 #include "speed.hpp"
 
+#include <iostream>
+
 namespace sakurajin{
     namespace unit_system{
         namespace common{

common/include/energy.hpp

@@ -6,6 +6,8 @@
 #include "acceleration.hpp"
 #include "force.hpp"
 
+#include <iostream>
+
 namespace sakurajin{
     namespace unit_system{
         namespace common{

common/include/force.hpp

@@ -5,6 +5,8 @@
 #include "momentum.hpp"
 #include "acceleration.hpp"
 
+#include <iostream>
+
 namespace sakurajin{
     namespace unit_system{
         namespace common{

common/include/momentum.hpp

@@ -4,6 +4,8 @@
 #include "speed.hpp"
 #include "mass.hpp"
 
+#include <iostream>
+
 namespace sakurajin{
     namespace unit_system{
         namespace common{

common/include/power.hpp

@@ -7,6 +7,8 @@
 #include "energy.hpp"
 #include "time.hpp"
 
+#include <iostream>
+
 namespace sakurajin {
     namespace unit_system {
         namespace common {

common/include/speed.hpp

@@ -4,6 +4,8 @@
 #include "length.hpp"
 #include "time.hpp"
 
+#include <iostream>
+
 namespace sakurajin{
     namespace unit_system{
         namespace common{