WEBVTT 00:00.080 --> 00:05.540 In this lesson, I'm going to do a quick recap about Chalcone and stay until the end, because I will 00:05.540 --> 00:10.310 show you also a new option that you can use to work faster with your Python nodes. 00:10.310 --> 00:17.270 So first of all, you have used Chalcone to build your workspace and I'm going to repeat that again. 00:17.270 --> 00:25.070 It's super important that you build inside the Ros2 workspace and not anywhere else. 00:25.100 --> 00:30.920 Okay, you go to the roster workspace and this is where you should have the source folder of your workspace. 00:30.920 --> 00:34.970 You don't build in the source folder, you don't build in any other package. 00:34.970 --> 00:36.650 You don't build anywhere else. 00:36.650 --> 00:41.240 You just build from this workspace roots place here. 00:41.270 --> 00:41.570 Okay. 00:41.600 --> 00:42.500 And how to build. 00:42.500 --> 00:50.780 Well, you do click on Space and Build and that's going to build all of the packages that you have inside 00:50.780 --> 00:51.950 the source folder. 00:52.100 --> 00:54.200 And here you can see we have two packages. 00:54.200 --> 01:00.080 Then we have also seen that you can add the packages select option. 01:00.080 --> 01:06.830 And you can only build one or well the list of packages that you provide here separated with a space. 01:06.830 --> 01:12.350 So for example my CP pg I only want to build that one. 01:12.380 --> 01:14.840 You see, I only built that one. 01:14.840 --> 01:15.320 Great. 01:15.320 --> 01:17.450 And now there is another option you can use. 01:17.450 --> 01:21.920 And that's going to be only for Python packages where you have Python node. 01:21.920 --> 01:36.500 So let's build the package this time my pi pg and we can add the option dash dash symlink dash install. 01:36.530 --> 01:39.500 You should also have the auto completion here as you can see. 01:39.500 --> 01:43.520 So let's build it like that okay. 01:43.550 --> 01:44.720 So it's going to work. 01:44.750 --> 01:45.620 Same thing. 01:45.620 --> 01:48.560 But now what does this option do. 01:48.590 --> 01:55.760 Well when you build the package with symlink install then when you do a roster run it's actually going 01:55.760 --> 02:03.410 to run the file directly that you have written in the source folder of your workspace, not in the install 02:03.410 --> 02:03.890 folder. 02:03.890 --> 02:06.170 And why would we want to do this? 02:06.170 --> 02:12.650 Because simply then you can edit your Python files and you can start them again without having to build 02:12.650 --> 02:14.270 your workspace again. 02:14.300 --> 02:21.650 I just want to give a quick warning before we try this is that sometimes it may lead to some issues 02:21.650 --> 02:22.220 and bugs. 02:22.250 --> 02:24.620 Okay, I've experienced that quite often. 02:24.620 --> 02:27.110 I've seen also a lot of people experience that. 02:27.110 --> 02:32.780 So if that option doesn't work well for you, then I just suggest not using it. 02:32.780 --> 02:38.240 And well, every time you just get the habit of doing a call on build and then source and then run. 02:38.240 --> 02:42.710 So let's open, I'm going to go to my workspace. 02:43.190 --> 02:45.170 So I go to the source repository. 02:45.170 --> 02:46.880 And then I do code that. 02:46.880 --> 02:48.560 Let's open the code. 02:49.730 --> 02:58.040 So let's go to uh here the Python my first node okay. 02:58.070 --> 02:59.120 Let's just run it. 02:59.120 --> 03:00.530 Let's see what we have. 03:00.530 --> 03:03.080 So I have built it okay. 03:03.110 --> 03:05.990 Now that I have built it I need to source it. 03:05.990 --> 03:13.190 So let's go here and let's do a source bashrc for example. 03:13.550 --> 03:18.800 And then rose to run my pi pg with pi node. 03:19.520 --> 03:25.940 And you see hello world and then hello space zero, space one, etc. so that's what we have for now. 03:25.940 --> 03:34.310 But now I'm going to edit and let's add, let's add some letters here okay I'm going to save the file. 03:34.310 --> 03:36.350 So you see I saved the file. 03:36.350 --> 03:38.120 And now I'm going to go back to the terminal. 03:38.120 --> 03:40.610 And let's try to run it again. 03:42.470 --> 03:43.610 And you see. 03:43.880 --> 03:48.920 So I'm going to press Ctrl C you see that we have the new version okay. 03:48.950 --> 03:56.090 So when we modify code here in the Python file we don't need to build again okay. 03:56.120 --> 03:59.420 You first need to build once anyway to install the nodes. 03:59.420 --> 04:03.770 So any new node that you create you need to build it and install it. 04:03.770 --> 04:07.940 But then with the Simulink install you can continue to develop your node. 04:07.940 --> 04:13.670 So your Python node and you can see you just save the file, you execute it again and you don't need 04:13.670 --> 04:16.160 to do any of the build again. 04:16.160 --> 04:21.170 So that can be quite useful to do some quick iterations when you are programming with Python. 04:21.170 --> 04:26.360 And of course it doesn't work with C plus plus, because any way you need to compile a C plus plus file 04:26.390 --> 04:27.950 to be able to run it. 04:27.980 --> 04:28.400 All right. 04:28.400 --> 04:30.980 So in this course I might use this option. 04:30.980 --> 04:33.590 I might not use it just now. 04:33.590 --> 04:39.320 You know that you can do a Simulink install that will be faster for you to develop Python files. 04:39.320 --> 04:42.830 And this is only good for development phase okay. 04:42.830 --> 04:48.440 If you're going to use your workspace in a more production mode, then you want to not use that option. 04:48.470 --> 04:48.620 Okay? 04:48.650 --> 04:52.340 You want to correctly install all of the files in the install folder. 04:52.340 --> 04:56.960 And also once again, if you have some bugs, because sometimes I've experienced that and other people 04:56.990 --> 04:57.470 too. 04:57.470 --> 05:02.150 If you have some bugs when you're using the Simulink install, then try to remove this. 05:02.150 --> 05:06.410 So try to build the package again without this option and see if it works better. 05:06.410 --> 05:12.320 And also only use that on Python packages, not on C plus plus packages or other packages. 05:12.350 --> 05:12.740 Okay. 05:12.740 --> 05:13.970 So well that's about it. 05:13.970 --> 05:15.290 About call code here. 05:15.290 --> 05:18.860 There is not much more that we will use in this course okay. 05:18.890 --> 05:21.650 So you know how to build where to build. 05:21.650 --> 05:24.170 And then the options that you can add.