Rust Programming Language Programmieren in Rust (Full lecture, German), 23 Nov 2016

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From YouTube: Programmieren in Rust (23.11.): Module, Crates und Cargo

Description

Vorlesung „Programmieren in Rust“ an der Universität Osnabrück im Wintersemester 2016/17.

Dies ist die Aufnahme des Beamerbildes sowie des Notebook-Mikrofons. Alternative Aufnahme (mit Dozentenvideo): https://video4.virtuos.uos.de/engage/theodul/ui/core.html?id=bac86875-bbeb-42dc-9970-55af51c9f017

Slides und weitere Informationen: https://github.com/LukasKalbertodt/programmieren-in-rust

Playlist: https://www.youtube.com/playlist?list=PL0Ur-09iGhpwMbNiVTBeHmIjs0GuIXhNg

A

We will not forget. That concludes with the modules and will also notice today, in particular, how we front code integration with us, so foreign so-called great, and we will look at what I will.

A

Program pretty much all the larger example that pretty much corresponds to what its tasks also So I think it should work quite well before we deal with it,, but before we.

A

Deal with it, a little addition to the topic we dealt with last time,, namely the one with news and colors. There's, another little trick,. You can't just do functions and modules and types yusen, but can also vary this. That means, if I have his name so the capital letters him on stands for some guy, then I can, for example, do what we do. That means for.

B

A

Variation in my name areas can address directly without a colon beforehand, point variant to say in the case another example, if token maybe still have a homework, some mariens in it and would like to write us a function. That does something with this token, for example, about match. If it is up to you that this token has a lot of variance, it's a bit annoying to always write token colon exams in the feces,. So we can tell these little tractors. Last houston, colon product.

C

A

And then we can just talk to the whole thing from now on, without printing the performance measurements, I can imagine similar problems like this normal forest tomcat. You have to use it somehow only sometimes, because especially a big inner has with that this whole morning area before when I.

C

A

Task so I formed the model solution, I actually didn’t fall for it. I somehow had one and another content, and the two of them wanted to use this trick here they told me straight away: no because of a name collision do n't, use them all at the same time, because both somehow had the same 1 band with the same name. So you have to be careful with that.

A

But, of course it's particularly useful if our little function has it like this one here,, where you really mainly take care of this dead person and don't have much else there,, you can use it to make the code a little smaller and it makes sense to use it sometimes for very,, very often used variance and to use it globally, so to speak. Joussen. Do you think of any of them berlins just right?

A

Maybe you were already wondering because he could up to now was always been could up to now and you can use it without letting the optical dictate it's exactly because of the options, the flag, salt in used globally. That means you can address them without always writing to the guy. The night before that's another little trick on the side that you sometimes use.

C

A

Different, at least why the.

D

Collectors can use it.

A

Now you can still have a bit of external trades already said, a greatest a compilation unit. That means this is a happen that the compiler processes in one go, and we have already noticed that somehow in the back of our minds, if they write a project that is not particularly big, we usually have exactly one trade for this project and how do you get? That would now be our trade and we already have it a little bit from the last time in brussels, nature with completely different motivated people sticking to it.

A

These are our modules they programmed the last time. This is our couch, and now I would like to ask the question now, but I still integrate foreign code. Foreign code is, let's say, sits in a foreign trade, so we were create as an aunt. There arises the question: how do I speak this create? This creighton now consists of a module tree itself and how do I say it now? Compiler.

C

A

Please take a module in which and through baumann the solution now simply that we, the model builders of the others in our module construction, sir, that would be the other craig with our own module. Construction, is now an example of a quite well-known, creating the system, and we want the mounting. That means we simply pack it under our roots.

A

It works with these. With these.

D

Instructions which we.

A

Will look at in a moment on file, and so you can create more about external mounts such as the city, library std, but you do n’t really have to insert them yourself. Somehow, you've already noticed that it's a completely strange thing to reattach points, and it's right now that we really hang them around our module tree,.

A

That means it's stranger, but we can enjoy it.

B

C

Much as standard.

A

Modules from us, that means.

C

A

It's due somewhere in my tot on a bed, more access and that's exactly how I could write the double pass. So that's external skin, but you can address it as if it's just modules of you, that's.

E

A

Bit so you have to get involved, but that's how it depends in addition to external coaches, also in his and his programs. Actually you can hang these external trades, so this external code, not only under the root module, but usually it is always under the root pension, rare cases you can also hang it under a different model. Assuming there is somehow an external trade, all of them provides functions to make cat calculations, and you can also do under this cat and a lot at.

C

A

Only this cap module has to do something with it, but maybe that will be addressed at the root, because most of what you use is used everywhere program says: ok, as said you do it like this to attach an external creighton and that hangs that, under our current.

C

A

Build makes it really comparable to a new module. It's not that big of a difference. We can at least use it like we're, making a module with the same name. Just the us campaign is now not looking for a file and then waters or a us,, but the compiler expects us to hand it over with a minus extern spot where the library can be found so for profumo to find it which we will see how it works.

A

But you can be reassured right away that would probably never have to be done. Manually, in fact,. I did what I'm about to do for the first time for this presentation,, so it doesn't seem to be that important,.

C

A

We still want to see how it works so that we can introduce something your folders and now.

B

A

Would like to somehow create two trades, I.e. two independent module trees and in one model we would like to use the other craig to create our creative pool for this I am just going to say: no, can you correct hello or greet and what we want to write in there? It is a function that should now become a library,, a krejci that can be used by other people, because we write in such useful functions and we just stood in.

A

This function just gives out so that the senate, maybe should say hello to me- already says right at this point: does someone happen to notice what you should then improve?

A

It must probably be parked as public us exactly because otherwise the me can be used from the create okay, but now have a completely normal function, who have declared a great package, and you could now use them here in this module,. But we don't do that because they use it elsewhere,. What if I mean that the rating gamers want to use it, and we would say that in slides have seen external create the plug ins, and now we are writing here, a completely normal journey, hello.

A

So far so good, but now a bit of a politician. How do we do that with the peiner? First accuse the greet of the mast compiler. What will the us campaign probably.

E

A

Exactly and filter functions so say that completely hey. We want to do something, but a library that is compellent initial to that is a pure real. Its execute is so hand over the flat rate and say then don't live trade. You can imagine great time, and now it works like that. We'll see now that in this folder we have our rs files, but there is also a point suffered.

A

This honor rib is a rast internal library, where almost itself stops the things that it needs. That means you might know dlls or points or in terms of files or something else like that from your operating system,. These are operating system-specific, libraries,, sometimes dynamically, with a static one,. That's not one of them. That means they can't be used with anything else yet,. So, of course you could call them from c or something else also say that we would like to have a library that franzi can call up, but that's enough for us.

A

For now we just want to stay under rust like that, and now we would say that cnrs happens. Yes now say: okay, ca, n't find this craig because said he expects us to do that by external handed over. That's why it was added and then just say, greet same lip advised against it.

A

A quarter took the beginning of this suffered the execution that works that also, we also have the execute images of these complexes correctly. Execute that on.

E

As expected that the.

A

Us computer always decides something that works best in this case is now pretty sure to work statically,, but you can say this one more time,, please link mechanically and the left, one statically and so on,, but that is a bit more difficult,, especially with the Leibis system going up,. So you knows the problem under linux. You want to be influenced somehow how a self- composed program should be flashed that sometimes leads to problems. Ok, sunday, questions about that we'll just continue here. I'll sit right now, because I'm doing several things right now here.

A

Here's that again example also slides. Let's talk very briefly about the standard library, I just showed on the square that you can also integrate this spd. I think you've used something from the city library at least a few times, and I think now all of them documentation searched.

A

But you noticed this city library: do n't, integrate with external, create that doesn't happen automatically that usually then the library spd for standard and away it should be short, the name of everyone automatically integrated by lastrup, so that you can then start the work and then maybe what you noticed I do n't know. Did you happen to take a look where vector lives and then you looked it up in the standard libraries? Did you take a look at the documentation for vector.

A

The grandson yes.

B

Exactly he lives.

A

Somewhere in this module spd, colon colon away colon colon gone, ok have that last then, really the the type so that lives somewhere under modules, but we can still always use the types otherwise the same with option and result. They also live in their modules, but how can it still be used automatically and there is a trick that is called blood and a preview of something that is used automatically.

A

So you press it immediately, but here again what the guest compiler does for almost every project that you compile cross compiler, that, at the top of the in the So, kate, will add a root module that adds this line, and then this is added in each module. It 's just the prelude from the city library, where everything is used automatically. That means you can always assume that we'll somehow add these two lines to something new program code has therefore could use quite a few things automatically I just opened the documentation for this trailer here.

A

So I looked for it and here you can see the module blood, and here it is also explained again so here it says: okay again, that will be a feeling of hate and then that makes it inserted and we can take a look at what's in the death, so there are several versions of it so that you can change something later. That's why this weird v1 and what's ultimately, only done here- the module just stands. This paper is in there. We may remember the last time we were able to change something, on sunday.

A

We export taboos again and that's exactly why it's done here. You can see that, for example, the way there is or the string director inside as that means this types can address them directly and also here all this variation of option. So we can use option, but we can also use cream and directly yes, a few other things that you may have seen before, so that somehow explains the magic behind it. We build everything already were able to use it.

B

A

In the city library, what is so important that 's the trick with the pilot.

A

A little hint you can of course, also deactivate the city library, and that is a system programming language. Should it be possible somehow the city library naturally accepts certain things that are in the city, library, for example, to network functionality, for example,. And if you are now on any hardware and any operating system,, then you cannot assume that you have provided network functionality,, which means that certain features of operating systems are expected in the library,, which is why you sometimes have to deactivate them. When you For example, writing an operating system.

A

Yourself will probably not happen in this course,. But if you write something very, very calm,, then you might want to deactivate this standard library as far as the state of the library is concerned,. So we know how we can combine these trades and can theoretically come to us, but I I've just said: I haven't done that myself yet, and he probably won't have to do it himself, because there is cargo.

A

Cargo is now several things, more tasks that takes on this in particular, but also a picture or a package manager who is also the official of gast gast For developers. That means that it is nothing if the ones already provided by the users and with cargo. You can ultimately create such cargo projects that have a certain directory structure and the end are mainly two things that are important,, namely once the cargo you write configurations in there and indicate the tendency and then in the folder source or actual source is also that would be a try.

A

Now so we want to create a cargo project for the first time it goes to all the simplest ones if we say cargo and then the name. I think I didn't particularly want to go to madrid, it's new like that, but there is automatically a library project pending. He will probably first want to have binary projects wanted to program.

A

That means you still want the spot there because handed over to later get an executable file that execute. Then we see it in folder for created, and there are things in there now little tip. If you have already created a folder and you want to create a project in the current folder in cargo project in you could use cargo in, but take a good look at what is going on in this way.

A

Then that you choose that.

C

A

So me I, don't know which of you has ever programmed ruby, on rails less well. Actually I thought everyone could somehow get into databases here. It's like this. In contrast to wii on rails, no huge directory tree is created here and there aren't 1000 files, actually only two files created and only one that he does n't know yet so we can have a look here is the cacophony, drummed and I just mentioned, and in the source folder. There is only one maine dot rs in it.

A

That's everything that's in there and we look at it differently now, when these files are in there. So one point that it is just e.g. cultures and in the cargo bommel it is in here. So somehow I think von automatically gets who you are, and then just says, like the great right now is called and lives here already such a lesson, the penalty action, but first we want to run the code normally and first combine it. So we have already seen there is just wild in it.

A

That means to do that now we can use the command cargo image and then there is a different task than with rsc,. So a long mistake, they come that the same as the barras c would come,. But here it is now said what is actually done, and now, let's see what happened, after two things came: about,, namely once one cargo dot log, the caro dot log. All things are stored in there or information is stored about which versions they are currently being used. In..

A

That is not very interesting for us at first,, but it is created in any case, and then this target folder is created where now there are a few other folders in there, and there are a lot of things there now. That is everything that arises when it is combined. We will also all dependency be in it later, and otherwise there is stuff here, so everything that is combined will be in there,, especially those executable file. This is this puppet exeter see here. I can run it now and yes, well then, what I expected happens.

A

It can be easier and we can say cargo, and that does exactly what we have to wait for combines and then executes So. If we.

B

Also change something here in the file,.

A

Which somehow new two and number can do, then also combined and for that directly.

C

From that I think.

A

First, everything that wanted to show now exactly because you will definitely notice that everything important is in it lies, and we will soon see a few more.

D

A

A

Than what I have just done- and there is also a complete documentation- cargo there- you can do quite a lot with it,. In particular, you can make good use of this configuration and configure a lot there as you sort of a make files could also make it just a bit nicer. Everything is there. I think it doesn't make that much sense.

A

If we talk it through completely, then you will rarely have anything to do anyway and then you can still read the documentation, but ask maybe cargo is good, but we didn't do anything with rocking seas. Now we'll have a look that works, we'll fix that at the cargo point without there we already have this stuff here that we've already seen we can just do.

A

One here add a new dependency, they say just drive the same 0.1 I just suggested when we form that then this happens here then updates a registry somewhere, then downloads a few things, and then it combines several strange things. What happened here this time is a trade, and this craig was so named on the official greatest drag race point. It is also provided by the developers, and there are uploaded, creates that you can easily use. That means you don't have to download them manually from gitta repositories or similar.

A

You can simply use them there addressing a name, for example,. This great time provides a few functionalities related to time, and these drives craig himself now have dependencies again,, as we can see,, for example, in c or vin ap. These things are needed, for example, to get the current time from the operating system fetch. So these are again dependency on the time and everything is combined.

A

So if we don't run any pictures teaches that, first, all the panels under which we don't have yet that combines the penalties and gives them the penalties via an external spot in ours, too application. That means we can simply write great time externally in our application at the top. Without having to do anything else, we simply write, and then it is automatically passed on to us kunzmann this trades euros.

A

To well then manually, the page is not very pretty that has to so I think at least unfortunately, but it fulfills its purpose. So there are always trades here, and there is a fixed name and it stands for a creator can also upload creates yourself, and yes, these are the most used trades are here.

A

You can now also craig if you go to something here,, for example, if he's looking for times, because you want to do something, we'll get to this- create right now and we're already seeing 12 million downloads and then there's a bit of information about the package or about the create, among other things,. It would be managed right now, and here you also have how you could selectively insert the cargo noticed that maybe after this point there is 35 behind or 30 m, who talk to the support.

A

What that means- and here are other things, what the create in turn depend on, such as this vin ap,, which of course will only be compiled. If you combine it on windows like I, just combined something else,, for example, probably just 32 and yes, as I said,.

A

There is just a bit of information about, what's going on and in particular jumped to the posse tory, then you can also look at the code there, and you can see that this is again just a cargo project, so here there is also a barren tunnel and a source folder. The other things are pretty irrelevant for that. What you want to do with it here, usually, there is more after writing, but we have already noticed here. There is also a link to the documentation.

A

That is very useful. If you want to use an external craig, what happens randomly in this task there, then it jumps right away about this. Documentation, which, as I said,, looks like the standard documentation, because everything is created with lost is the documentation,, so sometimes it is described nicely how to integrate it and that you then say external project here, and then you see here how in the city library what you can actually do with it so which trucks do I have here.

A

I seem to have these wrong ones, for example, and would like to click on them and see that, yes, you can call them up somehow and then a tm like that comes back, of course, not just through to to understand what exactly is happening, that tms instructors apparently has more fields and how to look at it.

B

A

Briefly, how it works, although I go back to my cargo points and will now add files here, but really only said 0.1, so maybe it worked it too fast. I just put the age away independence it action now. I can just say external great time up here, like I was promised, can print out this time here, for example, by showing parts will score in doubles, should go that way. You can any one hits back and is rack. I can hopefully also output, this debug output universe terminal go normal cargo brand execute.

A

We will help if you work with kaplan text, then will have a text in kago projects automatically combine things in the background. That means he complete it. There was already in the background to do some checks,, for example, the save there a little longer at first, but all the served you have to combine so now it has apparently finished. That's why it also worked in the terminal.

A

Something else was waiting because another cargo instance that just combined but ok, let's go back there you'll see if you installed this rost in hahn's, plugin and sablan will show up like this. All these compiler errors will.

A

Show up directly in your source code, and so, as I said, you have to use package control, install the package, and that means it says.

B

Snaps almost that.

A

Only happens if he works with a cargo project, so that's why I hadn't noticed it until now. I, don't know exactly why not, but it only happens in a cargo project. Yes, exactly then, when we say the koran again, he of course already has everything combined by sabra maus. So if we didn't see it here, but just about ps, it's finished, but then somehow the approximate of the monastery comes up so somehow seems to work a bit too bad. That has it already. Otherwise you would have seen okay.

A

He learns all the things under now, combined all the pensions, and now it's done, but now he has already loaded this create from the internet and it just works like that. I'm.

D

B

The presentation.

A

Now, let's talk very briefly about these strange version, numbers you've just seen. Sometimes it was said time, zero point, 1.35 and I simply put 0.1 and now we'll shoot briefly about cementing that's something. That's independent of rast, but which is often the case in new projects and a version number is often used in swim and aging consists of three parts and the first part is the so-called major version. That is something that indicates when a so-called breaking change happens. When you develop a leibi and you change it now.

A

The interface is, unfortunately, so that old programs that worked with the old library no longer work. Then it's a breaking change. That means, if we say hello there in our mini library beforehand, if we simply use the above function to say hello or something else, then that would be a break in change, of course,.

A

You rarely want to change your interfaces in any way so that you rarely have this breaking change, so that this library remains backwards, compatible for a very long time,, so you usually add new features and or something else,, namely this one version,, which is always increased when we make one add a feature somehow where we think it's worth increasing, that would be adding a feature somehow,, but it's still backwards. Compatible,.

A

That means something that doesn't destroy the previous ones for a long time, such as, if we added another function or something like that to our greet library that would yes do n't break existing programs.

A

Halo is still there, but we would make one of my version, the last full patch and that is always increased when a backwards compatible bug fix is made. That means there are often small bugs in this create. That means you always want to fix this when you have found a park and then publish a new version,, so you always hear this patch, this patch number, but not mine, because mine, you only want to increase for new features.

A

There is a special rule,, namely if the first digit 0 is just like in our time trade. So, first of all, you say that something like the great has n't been officially released, yet,, but that's still a problem, because most people who write their sick notes are always very reserved and are we afraid of the 1.0 version to publish, because we then think they would have obligations and something else, so you will see that a lot of trades start with zero. If that is the case, then shift the meaning shifts one place to the right.

A

That means the second place in blue is the major version and the third digit somehow fits mine and patch together,. That means, if I go from 0.2 to 0.3, then that's already a rüttgers incompatible, one backwards, incompatible change and in cargo points we actually always want to specify the major the major number. That means either just a number or if it starts with zero, no matter where our team trades, we say 0.1 in our case, because that way we can still get new updates, because we don't say it has to be zero point 1.35.

A

If we said that we would n't get new bug fixes at all, if he an internal 0.1, says we get new updates, but no updates that are backwards incompatible so that never breaks our craig. We could therefore also specify something like some vision of the create, but that would be bad if we could update ourselves a newer one at once download the version, but it is no longer backwards compatible. I have it makes sense that you only ever specify the major version thats why I only specified the 0.1.

A

Will we say a bit more about cable or show the live a bit more exciting I'm supposed to show everything? That's a binary trade, but you could make examples like this for library, trades, for example. So, far I'll.

A

Do it even better.

A

That'll, be our greet library and everything.

B

A

B

A

Source files for libraries will appear again automatically that in there are ready to say hello to us again just fit and the known. So this is now our library as a carbo project. You can also upload it directly to cargo, but we should learn to avoid that. This is a bad library and we want to not clear the name on cargo, so we can form that first, okay, but we can't run cargo rahn, because that's a library that means it can't run directly, but we can now, for example,.

A

We can add, plays to this library and to show users that you could use our line to do this. You make a lamp into a folder and create some detail on it. For example, what it is going to be like a good name use as well minimal examples, but let's just call it helau, and here we can then say extremely trade. So we use this example,. The examples show how to use the library that we are currently programming,.

A

So we can integrate it live with extra wide and then it must have a maine because it will be executable. And here you were also calling greet hello again. If you don't take a picture now, not much will happen the koran, nor will anything happen. We have to tell him about this special thing.

A

Example and I think called helau. He makes the example and then carries it out automatically. You can Since. There are several examples,.

A

The examples usually only consist of one file because they are supposed to be quite small examples,, so you can definitely do it with the example we have just seen,. There was already such an automatic test. Function, of course, libraries should be the best, have english tests in it so that they can always be tested automatically. I will add yours, our library can now that is, of course, the wrong file. That is the example of the witnesses. Our library can now test very very badly.

A

Then we deal with the output and then I'm fine do something more difficult. So I'll just write nonsense in it. We went to see if the computer still works and if we want to test it now, it 's just a matter of running the cargo test, and now it runs through all the tests and ours smells like it's run through. But then it stands here, something like doc test and there are zero tests. But somehow such dog tests are run and they show what that means.

A

He should now write a nice long documentation about functions that have in the interface.

A

You can't do much here a lot more to say, but you could also give an example here in the documentation, we'll just say: that's markt.de again as a reminder that something you somehow use on the top eleven that time where you somehow don't even know, put something an asterisk, then that’s music too, and if you put the 1 2 asterisk it’s written in bold and something in the way of giving an example here, use the same are taxi on github. Neither write comments in these weird way, tactics and say kinda, like that.

A

You can just use it like this. I 'm halfway unsure right now. It's an example of how it would be easier to write the documentation. Let's see if I've done it right now make a protest. Aha, yeah! Okay! There aren't that.

C

A

We have to take the test, make it a bit more complete by saying hello.

A

Now it worked,. That means, if you have such an example in a documentation that I offer, you will also see examples and documentation in the city, library, all the time,. Then it will automatically run through these examples and also test them completely helpful, so tests, whether compiling.

C

A

At all, I still have an offer.

D

A

Doc test is only compiled exactly otherwise. You just have the garden unit tests that test it.

A

If we want to clean our folder at some point, this can happen, especially if you are very have a lot of dependencies with a lot more dependencies. These days, the folders can be up to a hundred megabytes in size or something else we can just say team, and now we see there caps the agenda, it no longer say there. Space cargo picture then combine everything again, so it will be gone with carotene all old results so far and combined everything again, we will look at it again on sat 1.

A

Our trader used this time create have now also said karin and if I now say a nude picture, then we see everything that is actually happens because there will be several penalties. Combined. Download does n't have to, of course anymore because he downloaded it once and that's downloaded globally saved then bot. He probably wants a bit longer at some point and use figuration here.

A

I think that more or less everything, if I do that from one thing you can still do your contargo update, say the theater from this trade index again something in the new versions of our the penalties. That means, if just now, while I was talking about time, a new patch was closed and time now the version 0.1 point 36 has cargo would notice that now and would update the version accordingly, but that only incidentally and finally had one.

C

A

Thing that is pretty much still very much on performance, but if I've tried something now,, for example, your primtal test with all the numbers from 0 to 1 million or a load to test it may take a long time generally. It is so that the compiler and optimizes a bit complicated because the standard you can see here, if you mostly that happens automatically, because if we check if the Most of the time the image is faster, so then we can compile faster, but I.

A

Think what some at least some of you don't know is that compilers often have a lot of optimizations to do with the programs they control. When it's only dealing with java. You probably can't because he was all about that at colt and that's a bit weird, but compiler is racing again compiler or c++. Compiler use something like program, optimization, that's an extra step. That later I say just look at the produced program and look which things are superfluous, which things can I do faster and this program optimization is extremely powerful.

A

I would like to talk about it longer, but I think that's going to be a topic for the time being in any case, especially with money. This difference between and optimized and optimized is huge. You can. The huge difference is ultimately that when we use a load, I saw no abstract concepts, as we will see later. If you use any literature or anything else, then it is optimized. There are really a lot of objects, many method calls and so on, but the optimizer can make very, very highly optimized machine code out of it,.

A

That means we can then get very fast code, pretty quickly,. We can do that by saying at kago picture,. You then have the bug and duck release picture, the debug picture, as I said,, not optimized, that it is intended for the user precisely intended for the programmer.

A

The programmer doesn't always want to wait that long. We should combine that. But if we say this here then also compile normal dependencies release mode and if he just builds in program optimization, then there really are huge differences. So there are factors up to 100 are definitely possible, so from runtime. Here you simply runtime against combined time from. If you want to combine often you want to have short combined times, then you also have slower programs, but you can also tell the compiler to be strict,.

A

Then you have longer ones completes times, but come faster and willy's picture is simply that the user sends a game or whatever you want to do with his program. You can of course, do it as quickly as possible, because you can also take the time to read there form, although that's in in most cases it does n't really take much longer, but you'll probably stay in the back mode for the time being.

A

Yes, ok, I'll just leave.

B

That, in the background.

A

Right now I said already optimized. Yes, now you can see a difference because our program is so small, but later at some point we will see a larger example where that makes a difference. So you've told.

D

A

Everything here.

A

Exactly note, if you combine it with lars c, then you give it so fleck.

E

A

Also different levels exactly, but in most cases you want to you, haven't optimized or highly optimized.

E

A

So it corresponds to just an alias for.

E

23, no something like.

A

That, actually not no, you can maybe I don't know what the status is right now, but yes from a year or even that with many from iran. Also with sounds, it was like that it was 0 3 that has actually become slower. Sometimes that works at o2 are now such details. That’S why we do n’t really have to come. First, so got to know three tools that were just briefly compared. Then we would have everything right in our heads again, our usc, that is, of course the compiler, so the core of the whole thing.

A

We definitely need it somehow, but we will not necessarily always use it manually. The use is mainly limited to the fact that if we somehow very, we have small programs that usually consist of one module,. Then we use sc directly when we write small tests,.

A

If I want to hack something down for a course and don't have access to the playground, for example,, then I would also combine that with rast and raste is from other tools, but otherwise you will notice that as soon as you work on a somewhat larger project, betty actually always use cargo. This is, as I said, our picture tool and package manager and, of course, uses what c internally so calls the c, and that you can do almost everything, and especially as soon as you have any dependency that comes from from craig.

A

You don't want to do that without cargo, so we'll mostly bypass cargo. You speed off just again for comparison. That has nothing really to do with it. Now that's a full version manager. Some of he is surprised. You have installed the app who manages different versions of the compiler and cargo. That sometimes makes a lot of sense and in particular, offers the tools to combine floors. Does any of you know that cross compilation is okay?

A

Three people, maybe or so big compilation- means that one from one operating system, a host operating system such as windows, is combined with me, even if it looks kind of strange terminal linux, but it is windows that mandates the other operating system or another architecture. If I were to create another file for linux that I would give to a friend who works under linux, then I could set it up fairly easily with rast ab, so that you can do it.

A

That's amazingly easy, and anyone who has already programmed as e plus or c is actually used to the fact that it 's very, very difficult. This cross compete that in particular, raster interesting in rastatt very many different days, so different systems that are supported. I can combine here without problems for the rest of barry,. For example, that's a completely different processor architecture. So that's still poor, in contrast to x86, which we use on most normal desktops pcs have that I can just combine there machine code, out of which can be run on arms.

A

I can also combine for android without problems, and what is particularly interesting is that it was added recently. I can also combine to javascript, which seems extremely weird but yeah what there is actually becoming more and more important, because almost all of us still work with a browser. So.

D

A

Everything we do. We listen to music via the browser. We probably hardly have any of us any local music player anymore. If, then, you do it via youtube or even spotify or google play music or whatever javascript is becoming extremely important, and for the web to combine with extremely important and as we have more and more sophisticated web applications, we would like to have fast javascript code, which can be problematic with javascript. Once you have written javascript and there are there really approaches to optimize javascript code. Now there is.

A

Somehow sms that is a set of javascript. It was specially defined in such a way that the browser can optimize it if it sees it and races to it can combine.

A

That means we with our last code with a nice type of system, in contrast to javascript,, then compile that to mds with optimizations, and that is then quickly executed again by the compact browser, there.

A

You actually only have a loss of speed of about a factor of 2, in contrast to going to the local one and matif would run that's pretty amazing that you can actually do it, even though it's actually interpreted by the browser there's also wesley. It's still a bit new, but ok, I won't go any further. You can see there are possibilities.

A

Guest guest doesn't come only two executable to combine the operating system, but also very easy to other platforms, including the web, and that's what you use to install what compiler, for example, or to compile and at the very end I just wanted it was it just about fits in here talking about the different compiler versions and whenever a new compiler is released,. Although a so-called stable version is released, every six weeks, there is the stable compiler that we all probably use, and then there is the nike compiler, because actually something is coming.

A

What goes out of the official apropos story is pulled out and published every night, so that corresponds exactly to what people are currently working on. That is quite unstable. Often there are times when someone accidentally installs something and it was n't tested properly against any creates broken. Fortunately remember when he, but also early enough in particular, the mighty compiler also offers so-called unstable features that corresponded to features where the raster we could not agree exactly. Who really do not install the language.

A

Now we have such a full version for the time being of it and to be able to use it and play with it, but they are secretly fixed in it. That means you will sometimes, if you see any craig, you will see. Ok, have these unstable features or we have these functionalities, but they need a knightley compiler. Then you should mostly keep your hands off it, but there is a lot possible.

A

This label will be published every six weeks. That means at the moment we have this version. 1.3 10.0. Here too, is celtic version duck and right now there is also another version: the that the beta version, the there is always a newer version,, the stable version, that 's another six weeks to completely test the compiler again, and then there's this problem,, which is currently on 1.15 and every six weeks, as I've already mentioned,.

A

The next one will come on December 22nd version out where a few smaller things change again, then it all moves on happening every six weeks and, yes, you can imagine how long it has been around because we are over 1.13.

A

There are first questions about everything. I am doing right now, I said then I would start these sheets now. So he won't tell me I'd like to do about the same thing, you're doing that take a little solution from a task or convert my solution and that into a cargo project and build a module there, and you have to use it after an external craig to beautify your pokémon application a bit and that's exactly what I'll do here.

A

Only with the calculate is a little smaller I just need that with the recording, so that is now ready again.

A

Your task is a homework can of course, now with programming, but I think that doesn't make much sense right now, we'll just do it like this, I would probably just pre-program. The task is homework to create this cargo project, and I've also already written a task for who will tackle it best. If I am it's best to create an empty account project first and slowly, progress before really entering your coupon code, or in this case the cold which coach there is a picture of it.

A

We'll take a picture of it quite normally somehow tag, and I call it my dream is, of course a binary project that will happen. Maybe calculated. We would be in the folder and now have closer cargo project is not so exciting, now want to think about it. A little bit before I have already given you a task, how he wanted to structure it, but we have to think about it right now. We want to structure our directory tree.

A

We remember that we had several main types and main functions in our cold are delicious, once our maine, of course, somehow handles the whole input and output alexander otto kaiser and our parser, and this phase was also part of this expression. Expression tree. I think I'll just say here: let's create three different modules, because we.

A

A

A

That we have a consensus folder, where only this amount is.

B

A

We have to do it now, and this designation structure or this module structure.

A

I can already see that today is a very good day.

A

With the father, so in the songs folder, that means we create, for example, the file.

C

A

And the pictures, of course, with the place grows in the mine and the tax rate, nor the file express nor the pictures in the mail. We can already do.

B

A

A

Then that's interesting now, but it works somehow.

A

And that was still quite easy, but you want the bike. You definitely want to build this whole tree first, so that you don't always mix everything up now. We can then go over our code from cator to copy in there often.

A

A

B

B

A

Sometimes not a bit smaller, so I can copy big advantages better. We first copy everything that has to do with sex in six modules, e.g. the types token one types lexus and the function token ice like copy we put in here then a memory you can see. Some things are happening there that are not so good. We copy the maine and.

B

A

This red string once our men- it so our modules here a lot- will probably go wrong again, exactly and in more or less the rest of this here. So everything that does with expressions hedge fund express module.

A

Yes, almost everything here, if you happen to have looked at the sample solution here, there is still his tykwers integer, because I put 64 anyway, that's just in alias later to change, which internal computer bankett advised. I can simply write down 32, and now it changes everywhere in the coach, because I am everywhere in this code only the dough, however, otherwise have integers. They are like that. I would probably just put them in our mail so now that we have our new ones, tree- building, also simply pack it in the new one.

A

So now you can always proceed step by step to fix all errors. For example, there is everything open.

A

What do I have to tell us here, or what do I have to do at all and to be able to use this stalking.

A

Exactly really watch out, we then say newsmax.de and.

B

A

Just saved and one thing nice, as you saw before you private, as a function so in the alex purely and ignore that you can set all the errors, but this function for the first time, whether public and here we think we also want to set all these errors partners for all the types europa league. Then we also want to use them somehow selection of this module.

A

We save, and that goes away. Wonderful, then the problem is still. Okay is about the same, so we have to extra already use the type expression- and here are registered a pity. So you also here once papa prescription of expression rest also before op, when we notice that.

C

A

Use afterwards and terror.

A

If you go the crowds, then these springs go and the concert too. Actually, yes, because.

A

It doesn't surprise me yet somehow, but more on that later we're fine for now no more errors, then I think we can go to the other module now, for example, ex that will probably be a bit annoying on homework that we just have this error. Letting go add videos of the pope everywhere is, but now he's definitely suggesting that, then you don't have to do it that often so we have now.

A

So, let's see again that, unfortunately can't always say perfectly that 's wrong. He said, first of all, we can't whether the tires, because the variant number does not implement copy. We remember copy means that this type with. So if you copy the bikes that this type then also created a new valid instance for this is of course, all fields from my fall or all variance from my them also be copy. This barry and numbers is not copy. Why isn't that copy probability integer in it isn't copy, but we see here.

A

Ok, there does n't even know integer, then ca, n't, say if the copy is integrated in our root module used. How can we because then we can use integers,.

A

So what do we have to.

E

Write here again, the coach.

A

Or yes, that you wouldn't fall, exactly, then you would have to change several.

C

E

A

That's a little bit more difficult now,. Is it really like.

A

B

A

Finds how it was with hughes is always absolutely necessary, so use always depends on the top. That means it would n’t make any difference.

B

A

Could do that one great thing, but you don’t necessarily have to we start at the top, and the developer is yes already defined at the top and roots. That means we can actually just do. Yus integra sounds maybe a bit strange because we did n't even specify a bike there if it works like that, otherwise, no more errors, that's amazing, very nice, then this module jumps and from above through. We have the same problem with the intel here.

A

We also feel that there are even more errors, so we can't copy the tires again, then expected token doesn't implement copy and the same problem as before. He just doesn't know token. How can I now want tokens in my area dry? It alex defines.

A

That's easy lex. All these news, other instructions are usually at the top of the file. If you.

A

Want to limit them to just one function, of course,. You write them at the top of the function purely down below no more errors. It seems to be working and also in maine, no errors. Now.

A

Ok, let's see if he overlooked that we missed something for 14 days.

A

So I've already noticed everything this parts method or functions. This case is just private from expression. That means the we also have to finish it and.

B

A

Same applies to the world.

A

Now go form the missing form too. Then it actually works. It can just do cargo rank and yes, good, that it is already formed. It will not combine that again now. We can also do things directly.

A

Yes, okay, so far, so good. There are questions about this whole procedure. Well, then, if we install one more thing in this calculator,, namely we would like to display errors and results in different colors. You can see that the c or caro, for example, outputs, colored text here you might want to too given up colored text and we notice pretty quickly that it depends on the operating system and the terminal how your colored text turns out,. That means you didn’t actually want to program. It yourself.

A

Maybe you’ll just manage to get the color right for 180 percent of all terminals, but that’s it then also writing a very ugly co-trainer is so you think that with the color other people have probably had that problem. So there is hardly any cd. There is maybe on create one created, we'll have a look.

C

A

Trying it, just have a look terminal, I have to say the search is not very good on krejci. This is very limited because there are other sources.

A

Terminal this create is apparently no longer available for reasons yes, but only 700 thumbs is not particularly big, so you might not find that with this search, definitely find something quickly, but just give it a try. Maybe more will come. Then. Ok,.

D

A

Are also many trades here that mean that we can run colors on the terminal, but many you will notice say non windows platform that was I wouldn't have called that too. Not here now, but I also watched, is only for not windows and very popular is also that is not at all, looks listen. There is also very popular. What now stands out here in particular, is turn with somehow 600,000 downloads. This is one from the official rast developers library to do that. It's platform independent, but using that is a bit messy.

A

So we can now click on it here and look again here in the documentation, for example, how to use that- and we see here now that we need to get a terminal somewhere. First then need to call these functions on this terminal. Now, do the one in front of the ground color makes the green? Then we have to write to the terminal with this wide marco that is on green and so on.

A

So it is platform-independent and extremely useful, this library or this create, but it is very ugly to use if you wanted to do something with color quickly. That's why there are different other libraries like here, for example,, cold or other libraries that are nicer to use but uses, don't work where the terminals are, and that sounds stupid now, but actually this belongs to creating me and the used termin und gents. That means it is platform-independent.

A

I don't want to do any advertising now. You will probably still be careful, but if you want something platform-independent and don't want to use it directly, as far as I know,, that's actually the only source that does that if he, of course you are only interested in linux and every appointment now, you can also use other cracks fine. But now you would at some point these cage doses and we would like to include now we can use what you want after homework, but that's the best of course.

A

Here it is somehow the current version is from 2.2. Also, I have far too many 1 going to release the 1.0 version because it is always on the documentation.

A

I last looked at it six months ago or so from the next order, and now we want embedding that here is a bigger example,, but we're going to start with our knowledge and will these credits band mike us, and we have to open our conference from the tunnel and under the panels. It said in writing. It's just hanging I've just got it in the head. 0.2 so indicate the major version.

A

We can now somehow say: carl bildt.

B

A

Has to find out more now, but then just combined a few dependencies is your value, which immediately sees that the thermal baths will combine because thermal baths painter on it will be based after some time and look at it right away. But we can already look at this example here, a documentation. We have to declare this extern creator painter. First, that's pretty clear here. You go small peculiarity on germain written here with a minus, that's also a valid name for trades, but that's not written in roskow. It's so heavy.

A

You can't have a name so that there's a minus in it. That's why you have to use an underscore in the guest room instead. So if you ever use a craig with a hyphen there's an underscore in there, see what.

A

Happened to it. Okay, here we see already combined on the ground. Turn is of course, also based on some kernel or windows, api things to become 1 accordingly and is combined more seriously and then our colder. We will first simply copy this example very bluntly and put it in here in our nrs. So.

D

A

Trades are usually packed at the top, and I call this method maine two just so that it flies in our ears. Now ok expects it directly is not used, but it doesn't matter now do a lot of warnings like this, and now there is a colored output. You can see it's not really thick here. It 's because of my terminal translated, it's a bit special, which makes the whole thing a bit more complicated, but at least we have experience in the national example of exactly what happened, and we used print here with three placeholders.

A

Instead of writing these placeholders directly red rain or just writing yours directly anyway,, we have a red dot paint here and then wrote something in there. You will see that in detail later. You can do that with this, create think the documentation reveals that about but guttenberg it works. Now anyway, I remove the example here and call it proper again.

A

We see that here are some boards that we used. This to style must always be imported, for example,. It is also explained, and then let's import from kalla and attribute them variance attribute. We can save ourselves. We only want to have colors that, as I said,. You don't have to understand everything right away. That would all be in the documentation,, for example, that people do the same thing here. We would like to, for example,.

A

If an error happens, we output the error as red so naturally say here and in this error case we print out this error, but quite normally to express it now as red. You can look it up in the documentation or simply change from just said red paint and to what you want to print red.

A

We look directly that works, so if we now eight still works entering roth directly, you managed to integrate an external source very quickly with we want to expand that for this ebbo here too, and in the end it’s here too this overflow, that's a bit stupid to use. You can no longer just write this installed rey in there. If you want to output, something red,, the literary roth, you have to insert your placeholder and then use paint and specify this literate a bit stupid, but good. Finally, the result we still want green.

A

If everything went well when executing so we can say three, then a green comes out. Three years can say a green 9 or we can say peter or we can say something like that: a parenthesis on there. You can close. That's a road kids. Ask about that.

B

Good so again,.

A

To remind you what we did now got to know this week, how we can build up in modular construction, how we can speak any symbols from this module baumann with jus, for example, or with relative thread. We then got to know cargo and have just seen how we can look at external trades. Quite simply, caracol. Now everything down automatically combines everything automatically and so on it measures exactly what I just did. Pokémon requires a few more modules than I 've just programmed here, but ultimately you have to do the same thing.

A

Then I'd end up here, a little bit, we'll see each other on Monday.