Rust Programming Language Programmieren in Rust (Full lecture, German), 11 Nov 2016

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From YouTube: Programmieren in Rust (09.11.): Vector, match, Patterns and Enums

Description

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

Dies ist die Aufnahme des Beamerbildes sowie des Notebook-Mikrofons. Die Aufnahme der Raumkamera hat leider nicht ganz geklappt, daher gibt es kein Dozentenvideo.

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

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

A

I would say we distract you with something nice, such as rest. Think that the best thing you can do so we were found yesterday, a mother of god were still there and would have spoken the way already list, if you say so, I don't think link list of a list, be sequence, data tour that can be used in different ways. That is also constant use. Tasks is.

A

Then we saw other things and ultimately looked at: oh, yes, exactly how operated and what data we can already have. All that is already in the city library. I think.

B

That's all for.

A

Now it was clear as if you were going to do a few other things today, I said is he asks for so many small things that you might need, but that you probably don't really discuss like constants from tadics? You might want a constant career now on the council are all variables admire, youtube still just want to have constant like, e.g. or something else you could save in a variable, but you want to have your club and really decorate it as a constant. There are so it's easy with.

A

The keyword can then say the name of the constant and who is written in screaming snake case, and then there is the type under value we notice directly. We need the explicit type annotation here, in contrast to let bindings this has to be a grid for constants, since there is a philosophy that everything is somehow closed could belong to an interface, which could belong to a library, which another would like to use,. There should be explicit type annotations,.

A

So if I provide a matte library and define it more constantly,, then I would like to somehow know rectally what type it has,. So that all those who want to use them.

C

A

Unfortunately, this.

C

Is always necessary,.

A

You can also declare complex types,, I.e. any.

D

A

As constants, however,, you have to use this practically more quietly here,, so it is important with constants that they do not have a fixed address,, which somehow means that they do not really in memory, but that they are used everywhere,.

A

So if you use them somewhere,, this value is written directly by pi to the place in your source code, where you used it.

A

Stands but that is simply written by paula in her place,. That means it makes no sense to somehow create the reference to a constant, because that is anyway, only a constant that was used in this context,, so it always remembers when it is always newly inserted and I then said in scream. Snakes I'll be written,, but we.

D

Have to do this,, so this gives me.

A

A lot of pressure,, so this job,, which I unfortunately mean, I, use the fatteners,. That's not possible, for example, unfortunately,, we ca n't execute any functions,, so we can only somehow write in constants and constants also contain faltering, quieter where constants will arise. So, unfortunately that is not a bit annoying. But well you have to get used to it says already adjusted debtx, but we probably don’t need to act at all for the time being, very rare woman. They are.

E

About as detailed.

C

Easy with the Closing word done.

A

Also, the explicit tradition are also.

D

Global variables.

A

Which, however, have a fixed, a fixed address that sit in the executable like this string. Literary have spoken it, but extremely rarely.

D

You need it in particular,.

A

Maybe, with bad habits wanted to use a global variable. What we of course know everything what you should do, but that.

E

Is a burden, fortunately,.

B

Amazingly difficult to do that.

A

Schneider not now, that is on youtube. You can also define a news active, but accessing it is directly in the safe operation, because it is global. That means all pain can also access this variable at the same time,. That means, if you had a youtube, is the tig variable. Then it would be totally unsafe to deal with it,, but you do it.

B

A

Or c++ just like you're funny,, so if you just don't think about it, but of course it's very, very unsafe, so something else in terms of sport, so it has nothing to do with the previous one. Just a couple of things I think there can be. Then there were no questions us as if I would register you.

A

There are still. The palis where you can just sign up, can give a new name for a type with a type looks more like this. So if you think that we need a new name for the training, because we want to use the internals, then we can say it like this just say: type new name equals old name. There is, of course,.

B

Also, with even more meaningful.

A

Example, if he knows a way of it here, for example- and we would like him far away just so that in our project, nicer to read, is sometimes far away or interesting. Also, this possibility again the rx yes, so I have I not to use that now without the explicit action, but somehow the generic are a few meters above a guy, and this occurs with what like a second, are all creek. Mine is just a way de facto from the table so slaughtered rsn you want, so you can in any case new types.

A

No, so you can name other types already known types differently, because it.

B

Is so, you can now still use.

A

For example, so you can use this new name in the same way with the old name that doesn't matter in any so that it nowhere difference. Work is more important that works here. If you simply assign this character string to a variable of type string. That's just.

B

A

That's not another type else pays close attention to strong typing and does n't convert any type order into each other, but that's it the same type. That means we ca n't, somehow create a new type with it that I can sometimes make sense that you can, because here it wo n't, stop again. Nothing to do with the present. There are so-called type, is vacant opel and recognize jobs. What the difference again, what.

B

E

A

E

A

First, descent only called or something.

D

A

If you define us truck for the name, we then give.

E

The fields are.

A

Also considered, what guess he is dead fact is. Okay. I me text on youtube is exactly the intermediate wing that means about the name, but the fields don't have a name that makes are.

D

Rare but sometimes.

A

Look, for example, for this so of monday, writes that we do business bracketed and year falls, but name just do it under brackets and make a complete list of types there. We name.

B

A

Military force, there is not only one field, but that unnamed and why dedicate and senior types that is for this to set up this strong operating system. If we have any calculation, where we throw many physical units, for example,, then that would be quite nice, because I would use floss everywhere, but that we would really use.

B

A

That correspond to these units. What we can then do is say for these types with which other types they are to be multiplied and what kind of result will come out.

A

That means, if I somehow yes, if I still meters would have decided- and I want to divide that by seconds- I could define that it is somehow one of the last seconds it doesn't have its own unit, but you could define that it is somehow a speed of the summer, and so you can avoid certain mistakes, things that are at all, like meters, for example, per. Second there's no point, obviously that's why we.

B

Sometimes want.

A

To create such users that are patterns, that's also in other languages , we just rap an old guy and it becomes a youtuber and that's important here now when we create a second variable like that, we can't just convert that into 164. There are two.

B

Different types.

A

B

A

Superlatively 11.07, even where we'll go into this later. If you also understand how we can really do this, because if that's added from the other one out and stuff like that further, but these are already freuer, we can use these strong type systems quite well there. You need fewer.

B

Errors because.

A

Everything is already compiled to check are, but complete, be exactly the paradise pope says that is steep. Is the field in this.

F

B

Be Of course it's.

A

Not necessary because it 's all on one module again,, but if you really did this idiom, this pattern from youtube,, which I'm climbing right now, you'll, also do it privately, yes,, but then you would write a whole lot of other helper function. Methods to access it was now in any of these tracks are like struck real guys. That means we can always copy, and here we are an example where a truck in two fields is, as said, just a separate list, and the two will now not patrik the fields, but that's hardly necessary.

A

I have another thing somewhere here I linked to you that was explained a bit again. It's hardly necessary mainly if the office of the work for these new times has more than one field in tube instructors, extremely rare. So far, it's.

B

D

What I'm doing.

B

A

That individual other type definition but there's a whole bunch. We can describe developers it's almost up to draxinger that they don't name forests. Okay, then, let's go to match at the following times. So you know it case from mainburg. Manna or other spoke your account and it would like to because there is such a switch casemod switches. There is no burden. What is there ne sch and matches quasi switch case. Only looks better that you.

D

That you, the syntax from we.

A

Have the power supply here, then you get the argument. What we notice that we want people then come his series of so-called match arms. These arms always consist of a left climb and the entire session roppels. The said sign is much larger and then somehow the armed bodies come on the torso. They.

B

A

Separated by a comma- and then we can already see here that this is used as in expression, this whole match blog is an expression, so the value is evaluated and the result is then these last experts of each arm and what comes back at the concerts output and can then output.

A

That for us is first of all a comparison between katherine later, that is much more powerful than agent kay. What else stands out.

C

A

Ask you what is finished yet on what is there still a lot of difference to the case.

A

Exactly that actually makes sense, because no one is like that, then you write in switch case in other sections without a break at the end of a blog. You hardly do it in the days of c the guest used to have a few applications for it, and now, even if you just now, there are numbers in.

D

A

Science accordingly task reminds you to output a number, so that's exactly where it sometimes makes. You see that you can simply.

D

Write several cases to.

A

Each other you can somehow use.

A

A colon and here's a mean that.

B

Does that in, but if we.

A

Also happen other possibilities. What to do so. That's it that you.

D

A

That corresponded in particular to something like java. It's actually nonsense that there's an action as well,. I already said that can use the rock, for example,. There are several other options, and I said that even if I already said where it exists,, especially important.

B

A

In contrast,, all cases must cover so here are different. I think you can already think what it is. That's a the joy case you would say with switch & case. That means you always end.

B

A

You don't enter the first one or the other has, and we have.

B

To do that because we always have to cover.

A

All cases in matches it might seem a bit strange because we are still interested in a few cases, but in most cases it makes sense that we have to do these expressions,.

B

A

Arm sleeves, they can also be in blocks, so I now says.

D

These are expressions here.

A

Again on the right, but we know that expert albert böcker wants to delete. You can write down. We are here hole in shapes brackets. We can then do several things and do several things and his number don't want to do anything write again. For example,.

D

A

What might be noticeable when the blocks write, then you do n't actually have to formally decide this at the end so to separate the individual, but from each other that it's not necessary. There is more that people can have. I already promised, but we have now given a time to your pieces. We would like to find out what is normal to eat, and now there is this and ex-husband is.

D

B

To imagine that.

D

A

Power comes when eight or nine rows come the match. Then this arm is taken. You can simply use this symbol to combine several alternative patterns and tell her because individual cases apply then you can go in here. Then there are granges. Look like that. We must be nice, because now we might notice three points and not two points like infor loops that are included.

A

If that is also the right part is inclusive, so 15 pictures also go in lahnstein, and these rangers are only possible in matches that something I don't like any other way, and there is a big debate about it. There are now point rangers that you can use to strip him in front of you. For example, you can use at this point point point parts that you can use to match hits that.

B

Is very, very inconsistent.

A

But with that, you don't have to do that, because you.

G

A

Have to get three points inside so you can't calculate the exclusive in the match on the grandchildren, as I said it doesn't make any sense. I also find it extremely worrying.

A

And then we have here again because the joy case we always need what we can still do more syntax so matches there. We have some on sundays. I know the end of the season. 0.

E

A

100 helps is from m, you can imagine what it does just to read. National pattern has such as a range you can by name peter there one evening, so we can so here.

B

We can don't access.

A

These, what it actually is, we can.

B

A

Limit between 0 and 100, but if it were n't, even what that is so used when you put the name on it and then later check it with a so-called match sheet. That's just my additional condition that comes behind it. Whether this ending is a prime.

A

They are hot to.

D

Clarify the line.

A

It looks on the whole, but we can then just now or committed always.

B

A

Match- and we can have at the end after his match, gave where we can decide any terms. What you.

D

A

Now, okay, that's who could maybe think about it for five minutes now come on that's now. There are some problems if we can write any work under fair conditions, no rast compiler for us, of course, not check if this match covers all cases. So so, if it's prime always give back, I would think of another example say the angel. Only the cases with msn skype or, let's say similar, praise happy. These are the two functions. We wrote a compiler ca n't know that there are only these two classes of numbers.

A

The can't know that one function returns when the other one returns fully. The compiler can't always say exactly whether we've already covered all cases,, which means sometimes we have to make a few decisions, even though it 's actually not necessary where we know that it never will can occur, but that's rarely the case only.

B

A

You've already seen a bit of.

H

Bad luck so, first of.

A

All the variable.

C

B

A

On which people have written a 23 directly to the top, it's variable, but here it's directly like that. We have several.

B

Options can go.

A

B

A

Is plugged in it now just stands for iris, peter 1900. That means plus point is the value will be higher than the people in this range. If, yes,.

D

Then please put that name.

A

On it first and then see if the butcher says that is correct, so the match has that the shoe delivers back. If so, then,.

B

A

It happened this year, then it is so. Nothing else goes to the next arm and see what happens there, and this is already the people's well-being, then just run every.

H

100 lies the pace and if it is in the appropriate council and no pc issued exactly.

A

Why, in a full we are, we have no window between 0 and came.

E

On the right before.

B

Yes, just like butchers.

A

Generally, pay for the whole evening.

A

How come you end up with a name now? So if you happened now,.

F

A

F

Known yet that's why.

A

You have to find that by a name, so I mean often you have it so that you say, for example, we.

C

A

Kinda latics easy 1, 2, 3 and matt __ ] that you have a.

B

Variable in front of.

A

You and then about this variable man. That's you, but overall, a case where it's just a number: that's not 64 or something like that. That's no.

B

A

Recognizes this here that omit- and you say, here's fix, but if.

B

A

About it again, don't tip strings,, for example, the.

D

Streamripper before loops in this match,.

A

Blog calls, if we specify it here,. That means we could.

D

A

It less, of course, you can of course have entered a name for the string, here, I know it sounds very complicated, otherwise once see a few examples, but believe you always want to tie to the thing that is actually more on the match. First of all, it might not work.

B

A

As I said, I should have described it again with Peter's syntax. Very precisely, then, maybe it will be a bit more. It's clearer how it's coming about now. I can immediately. What's the same here, are the taxis between the two one? First: keep it up. Peter I've already promised that a few times the patterns are important to us in many places, and first of.

B

All distinguish.

A

Between two types of fathers there are other things: youtube are the ones that don't always fit and that misleads misleaders. That means one always as always, be careful to be just what.

C

You've seen everything is.

A

Advises oppel pattern, for example: 3 that's a pattern, but that does n't always obviously fit when the variable is not always 3. But if we want to write it has a name that always fits a name is always valid. That.

D

A

An example right away, so parents are first of all you can imagine that trees. We can somehow have several nodes.

B

A

At some point we sheets and at the end of these sheets they are either poor or literate. That means here, for example, a here, be a pattern, and here we see two end points that unique. That is now a name and then here a veteran shoe.

A

D

A

Special names underscore to ignore names. That means we bind the name to an underscore, but just ignore it immediately, and the important thing is that here too far, you use the total. The pattern commands that you now think briefly about why that is so. If I do it again, for example, before we think of these two felling.

A

Erected on you don't have to imagine everything.

B

A

B

A

To 5, then does something and something else.

B

A

Scroll is now called youtube because that only fits if it's worth it, if he's between three and five is between 53 and the last pattern is always so. This people money follows case. We built in always have a youtube pattern, so a pattern that always fits. Then it's just a name. We can also write ex here then, by the way, will he, but would this aura be bound to nothing?

A

The name is simply found in this value, which then this serom is floating. But then you say you have a variable that you don't use is nothing so just say underline becker the compiler won't say that either see an example right away. I hope, then everything will be clearer, that there is a larger piece for the festival we had that until now, if the literati have in the maritime. Otherwise, if it only consists of the name, then it is always understandable.

C

A

Now we have just that were now the leaves on this tree are falling with the weather. Now, let's take care of the inner knots, so the the other sons- and these are the sun- get structuring structures so.

B

A

You structures have a type in any way, can the destruction that is remove this structure and evening then letter for each individual tooth. The individual slot in this structure, for example, that one now, for example, we are already- we can do until the structured its already seen. We can instead.

A

Describe sometime, we can, if we have a title, we can so remove this structure from the hustle and bustle like structure and then has the reliable of slots I'll call where we can build another club again in this case, these other peppers look directly at the leaves. So here's the name.

D

A

Choice many faces.

A

Look, I hope. With the same you example, it becomes clear you.

B

Can also references away from structure and that.

A

Is also a structure.

B

A

You somehow have the same slides if you have a reference type on the right side, and you want to be able to apply that to a pattern on the left that in this pattern to this one and and and write down and can remove this reference. There is on youtube in scrubs that looks similar to dolls and that you prescribe the name or- and there is also for spite, looks like this.

A

So basically, the pieces are hot and there are several slots, so the fields from which will again be named Lindenbaum, for example,, both of them.

D

A

Have one more point for the sake of completeness,, which means we want to ignore all other fields.

A

Comes the guide later now more examples. So this time we have a good law, a cloth from istanbul. Now he can via ixmation. It could, for example, write down an arm where we drive two constant, two liter pallets 0 and if the arm, so this pattern is bad because it does n't always fit, but this work.

B

Is taken exactly when.

A

This stage contains life 0 and, if that's maybe not too exciting, but we can also mix with it. So that's.

B

Already this bacterium, but here.

A

As always after constants or better said, it can.

D

A

Also say that the second is the first we find a name, so we now have two slots and can insert something, namely again a pattern and then the chance there have now a literate added to this name. This name will.

B

A

This value found that flies like this, and that would either use it here, so it would be issued then 27.

A

More is clear, I think I 'll do it quite slowly, then the game can move in tomorrow and can still do that. Is, for example, another scroll to write, because if you look at them they are not exhaustive. Yet there are still cases that have not been covered, and in this case that.

B

A

The us computer and that's why you can do it in such a way that they say no matter what recycling is here. Actually it doesn't really mean that itself we don't care but win that make this funny underscore and the monthly salary doesn't matter. But it's not a special symbol to say we don't care its just a name, the other. We are variable m by the way. We then also know that this here, what we are ignoring right now, that can only be full who the tool.

B

A

Been if we had already entered here in the blog slight nod, sometimes that is very courageous, more examples. We want this friend human beings. So at some point we have a point in this case. It is just this one origin.

D

The one already.

A

The I don't have I have here, of course, somehow, and we want people that means we could now break up this district destruction. It's like that with these are. What does that mean? Now that doesn't mean go in the slot for the field iks there? We, then a liter of choice means something else like sarcasm, 000 being, then there is.

E

Also, the fantasy.

A

Lawn that is also very fast, but no neutral ones write there now, but we say that here too, it is simply accepted. That means then we can use it here, and then that means somehow we are on the on the y-axis. Exactly 10 is a pcie long. Only then does this to me. This is another one.

D

A

Quite many are 60 different case and if we want to tie this this field to a name, but the name should be.

D

On that doesn't mean.

A

That the name comes up. Actually, this is just a shortcut for y y.

F

A

What you need, sometimes, when you think than me, because the game world that you 're just embarrassing markets on this axis, where x3 than there are special things that somehow that means you do n't want to name it somehow,, but somehow position wall or that's it, because the semantic makes more sense.

B

To you now, after.

A

This case not a.

E

Perfect example, but at the beginning you just want to say a better example. The name outside of metz is unbelievable. You will otherwise get the name. You can't calculate change the name here,. That's.

A

Exactly that, for example,, if you have already.

D

A

A y here,, a y that is not related to this point, but you would like y,. Then we would create this name here.

E

A

Can use with the outer name.

A

And here we have the default case again, but this time the point was income because I.

D

Have written this point here again.

A

Directly here in the match, instead of previously creating a variable here,.

B

That bind to a name.

A

And output types at all, I can do that. Then I would like to ask you again to ask all the questions you have about. It. It doesn't look like it will be convinced.

A

Always compares whether this skater doesn't apply if we have a youtube parent which doesn't always apply, and then it has to be a chat and then it'll be fine, whether that fits so this point is actually x0 enduro.

D

A

Temple patterns like the last.

B

A

Here then, you fall on everyone case, one. That is then as follows case. So.

E

B

A

First understand others.

G

Then maybe that’s how it is right that you need this innovation that we had before, where you exactly behind the people.

A

Overall, you only need it if that’s a range, because I know it's complicated now everything is.

B

Correctly recognized again.

A

If we eg here, if the liberal is different, if we write here in the name, then you don't need this reputation at all, because we've already noticed if we have a writer but such a parade week, the name too not because we know what will be found.

C

A

The only thing.

B

A

Is if we have rangers that's one for later, without a name that means only for rangers. You need this about station by station. You rarely actually need.

B

A

Question you should just ask Reported.

C

Simply because it broke at the end or is the variable later normal.

A

C

A

Example, text the.

C

C

Can write underlined from because.

A

Yes, too,, if we then no longer want to use the point at all.

B

If we want to use.

A

This data in any way, we then have to take it, tie to it as.

C

Kohlers or hot, or has one last way, and if you don't step in now and write, then everything will pass by.

D

The island a little later just.

C

Right for that, this.

A

Renaming is good that we just want to leave it to peter, then we'll do a few examples. If that we here today means origin, what will come out then? What does the program do then that you think about it? That is best for everyone who is currently thinking actively, because it is clear that the new lower part, also in the upper ones.

B

E

Bring the olives and thus, in any case, ok.

A

Exactly what is a match seen so evaluated.

G

Origin function.

A

Is that itself still zero points?

A

A

A

A

A

A

A

A

We now others like, for example, that is not what syntax I write a table so short, but.

B

B

B

B

The left just stands.

B

A

And trained they are not behind or feel then is or peter. Then, of course we could not planned or spend peter can not spend the y. Angela of our point, if we would have underscored, would decide so again, no sense above all, then could have we back here. I put out.

B

B

C

C

C

C

A

Right so, first, what we switch up here that will be called into the match. That means it now belongs in the match, and then we can get ownership back to us by tying. The name to it means suppose friend would not be a copy type now, but would have sample text. Then it would be so.

B

A

Then again, our garden, namely just took it suppose the poet now not 64 fields but string fields. You do it all the way, but so that we, a non- cognitive fields of work, then would we.

B

A

Regained ownership of one of these fields, here, for example,, which neither found names if we were to write here with different ones or anything else,. The signature from the eight to another field is lost because we do n't seem interested in this field to bind,.

B

A

Push the ownership into the person and then the ownership can get stuck on the individual pattern. Again,.

B

Okay, I'll go.

A

To the next step, I hope, I'll have more examples right, away,. This binding means that you will always write the name to the other properties. You.

B

Can think of one.

A

Property, we have already met.

B

Exactly nude the picture key.

A

B

Will all be written flags? That's.

A

Why, until now, this has always.

A

Written to me, what for us like special syntax selection of the latin music or something else true to the name what's important, is that it doesn't refer to the leg.

D

A

For example, what is being reduced,, I think.

D

A

Had asked that now or the penultimate time, that would be almost almost sorry dealt with exactly what it means, but.

B

A

Property of binding. That means that has nothing to do with the variable itself, in particular, if we could, for example, start it right away and then.

A

Drink so a new boss is not here with youtube. Now we know, but just say afterwards: okay, we transfer the signature so.

C

A

So if the first sh this as a is no longer used after that are transferred without bubbles, it usually looks at it the same name. You can use the old name less. You can also have said directly about create, and now we can change. The modifiability is not a property of value, but only value right from the start. That.

B

Means we can always let you.

A

Back and forth about banks, or if you.

B

C

A

Good example, for example,, if he.

A

Lowers his function to the green you take ownership, do n't make a reference to yourself in that either takes over the ownership string. Then you try the.

B

A

A

Surprised that.

C

B

A

Council and says I have the different build the part I ca, n't change that if you had his dear fans or one so if you save in the steppe save now, of course, also not more then, but less on a help saved. You will find that even doing that seems somehow strange is still thinking about taking ownership rather means that a youtube de france, if met on youtube, could change it. But of course we have sms or chips most of it. What you can drive, but it's.

D

E

A

It's a leg: this leg is n't minute. That means we can say here in advance. It's.

A

Enough and then it could change it, which is in the usability just depends on this binding, and we can do that always around.

E

A

E

A

That's a bit, so that's not a bit nicer. You always have to do it see like a right here before that already in the argument list. We also just have a pattern on the left side. That means it also feels names in front one writing down that works right.

H

B

H

A plate on the left side maybe write again and then forgot did n't use it anymore. But it's.

A

Missing it's just right, then it's back on youtube. The pattern can.

D

A

Seen by the way, sometimes, if you have a, has a longer function and you need a few values of our calculation, so it is ing, says my main, a rhythm and before that we need a value, but we need to calculate whether the calculation of the value is not entirely trivial.

A

So we need somehow in this case then, for these values for the first time musical repair around the allegedly changed snow or something like, for example, the number of operations in quests all clear that display nanovation, but tell me for because it is in our main function. Then we have to proofread this counter as a youtube. But then, once we have calculated it, we don't want to change the main algorithm later at all,. Then you can.

B

See exactly this pattern,.

A

Which is quite simply new wine,, but is positioned later on youtube,, not accidentally changed,. There is.

B

A

Way to do something, now the price question, I, don't know. If you can make this a bit nicer that you want something new to youtube.

A

It is always a precalculated clock that needs a value should later be meant in terms of design patterns.

A

I would rather.

D

Be too simple before the.

A

A

And here we have some musicals.

A

A

To do some calculation for that the musical has to be, and at the very end of this blog stein fx with this youtube, ossenberg, homemade and saved back to this sp, which is now in jubilation it has. The additional advantage is, has all temporary variables. The rings are at all. We are no longer in the scope here,, because something has to start at all,.

A

I think that's a good thing,, but I.

B

A

I've moved quite far away from the actual topic, mobility definitely fits. There are two other things that we remember from the name be able to write, and that gets even more confusing red.

A

That means that this name is not directly linked to the value, but to a reference and rap courage. That means that the name is not linked to valuables a meet the trends, whether you've finished and will have an example, a formal, the 32 variable. Now, let's do this here of the coop, doesn't matter how its fine say lips, I lon would say xy away, would yes, the differences be transferred, or in this case, strips are compatible, is simply copied and y would be on opti 32 in any case, but since.

B

A

Rips I lon news: how do you think the last tier low priority we could we this whole pattern can also always leave pattern, so this meeting is not for the last time y.

A

Exactly now, it is of the type reference to the 32 same. Can we with his youtube compatriot? We can use this difference to change the original, for example, and the scope is, of course only there for this code to be composed. Otherwise the eu would have complained about it. Is there is a good balance, youtube.

H

That can be done.

A

In the same way, in this case absolutely pointless, but we'll see later that you're.

A

Wasting, for example, I think I'm guessing a league, for example,, who are me from the past ring and.

B

A

But we have is a function that now also gets this doll in, but only as a reference, because this, the opel shouldn't, have a function, but just take a quick look at it. So we'll get it does alone is a reference thing and 1 64, for example. Clearly so and now from people to do different things and in one case I would like to say, for example,.

A

If that is actually ps or a fraction of it, then we would like to output the string, something something.

B

A

And otherwise we just don’t want to do anything at all. So what is that? A lot will happen.

A

B

A

We can refer to references people that ’s no problem in this case, then ownership the reference not from what is referenced but from the reference itself from the pointer is given in the match, which is not a problem now, but the problem is that we have here in the match, pattern of completely different types. This pattern is of the type tu of string and 64, but in the match we entered a reference to a hustle and bustle of string below 64. That means we get it.

A

Otherwise we can solve it in two ways: either there are still many faces up to.

E

A

D

A

Right the faces will do well for that. So far, We can reference this reference,, which means we get. What is behind the referent and give this to this match, screaming about this transfer of ownership is lazy, however,, which means it is not done immediately on the spot,, but only if it is actually necessary later means, for example,. The compiler would not complain at all, because we look behind what is actually differentiated and give ownership of it to the match,, but it is not really used.

A

That's lacie only when it's actually used, something happens and we use it never like that, but has to. But what happens now with this line.

E

A

Suddenly have this it bound to this string, although we wo n't actually need it at all. Maybe you can just guess what is necessary. Then we write it there.

A

So if we have some simple pattern where we can determine the right side and only talk about the whole part about reference or non- reference, then here on the right side, my circular can be written in such a case where you do the structuring and want to bind new parts. Somehow, then need this meet pattern.

A

How can we'll fix that again without this strength, this match someone.

B

A

Also references gone destruction that we write there. The pattern is now of the right type. Again. The pattern is of the type reference to title of string and 64. This reference, tuesday gone again actually, but.

D

A

It's always so that you want to write an asterisk here, because you can imagine that there are many, many poor people here and then you always write this and before that, a little more me, that's why you actually write this up there for that we need it this right. As far as clear the example just continue here,.

A

Only if you happen to hit a bum, the structured asset, the structured up to, for example, and then you do n't want to transfer ownership, but I rely on. We have to what was already mentioned last week. What this with buy a surprise.

A

Means explaining something that was the question: emotion, youtuber reference, what it was there, the difference between the judt here and so on. That was a bit for turned we're going to look at it again. Here we have with the city and two xyz and xp tier were said for a long time. It should be linked to youtube. It means this six prevents the value in 32, 32 and memory, and iks now designates the memory 32 directly.

A

The nude now means that we change the memory we'll do that this here. The english referee is not the best referee, but it is what happens will happen. That is, will he be on youtube plans, jst and y? It will be the y both teams to the difference. That means at some point memory now sits the memory address of, but this saves this this pointer. We designate it with y.

A

That means we can change this in herbs. We can change, but today.

B

A

On youtube or my friends, that means we can't change what it points to. We can't do.

D

A

So we widmann b that's happening and.

D

Then pointing it out to new.

A

Ones, that's not possible because that's an internal staircase refrains. We can't change the referee so what's being shown, but what we can do is bend ypsilanti reference to z, for example,, because.

A

A

C

C

C

C

A

These stars franz yours, that won't necessarily be the signature. That's a bit more difficult. What happened here is just it's difficult to explain this bit here is of type ii 32 years. That's why we can also assign the 32 teams. That's called one.

B

A

Value something that can stand to the left of the same times. That means rené doesn’t immediately have ownership but will have something floating.

B

A

Air, where we already have the right memory address at hand the 15 point to it. The.

D

Refinancing is not.

A

Necessarily ownership directly transferred that only happens if it was, for example, grabbed directly by a leg lengths.

A

It was maybe I didn't quite understand it, but maybe I didn't put it quite right. So.

B

A

Particular also tells this xs minute or not. He cried it didn't matter, because here wild, we like that or such a wetab in cheering fans sixx. That means, if you, the officers and the full tent to show a new value, the kind of reference guy so in gear or not and don't want to are you're my form, keep others away and watch it again. How to.

D

A

That tenants cheapest, we can change the 32 with the name xe and now it's different. So it's ypsilanti, it's not just about dressing up but forming a thriller trance on xp. That means now.

D

A

That we can change what Germany shows, but we can you ca, n't, always bend it yourself, that's okay, because you can finance change a value behind it, but we can't do that here and just as a note lately are very, very rare. That's what I want that you never really need it. Just so.

D

A

Once you understand this sorrow hangs, you can then get the house attacked. Do.

B

You already have.

A

Any questions about it or should I continue? First okay, you should continue.

D

A

D

A

Use this peter annually at four points: that's why they are so important. We can do them, for example, use lag with links and.

B

A

Use this of the rankings that we already had here with the y mentioned, for example, that works without any problems, though patterns are now the netbank, a special kind of climbing. What do you think.

A

E

Sort of always work exactly.

A

That's the handle youtube pattern.

B

Of course, we can't remember peter the departing only works, sometimes when.

A

Doing something we're not evangelized, it's not entirely clear what happens then, so you ca, n't continue. That means it always has to be on youtube. One for a range of functions, also boards that I already know how to say here easily or briefly. If.

B

A

A function 95, twitter, brawn-mercedes traction or you will exactly you.

B

Can now your reference way, destruction and.

A

Here too, you need a pattern on youtube. There we have, there are no other options,, it has to work,. That means we can't write any liberals into the proposal, by the way,. I also showed that at the very beginning that we would first grind the funny syntax peter linden in rain of coincidences,.

A

That's why we said we were through one reference to a ray ban cheer. That means first.

D

Of all the elements of this are spat out.

A

The suggestions are also reference types and then also dolts. That means we don't take. Two destruction ring steps once at the conference and then only slowly, your scruples, that were also that must be your sayings.

A

There's a series of things that are coming up for youtube: ipad, that 's a match, but also the so-called spread and wild. That's a.

A

Brief discussion: first, that's only on sundays, even for match are familiar with the term, but that's just one intrexx. This makes certain things easier to do that you could do before. So we already have all the options we need with match. The flat and violet is just bigger for us. Sometimes that is, for example. So here is another pattern. Sorry in a pond that means to- and we now want to see if this match does that to me too, that writing patrick sercu is nice and then a possibly was feed.

A

Influence doesn't always have to work out and in this block against us exactly when the match, because it's.

B

Exactly Of course that can.

A

Still be 12 karben, while at looks similar, we'll see how that corresponds to the match and that corresponds to match. Then you might understand that better. These two are extra already alex. That corresponds to a match via the expression where we have each other. Please pattern in this weather, then this hull, this buddy, is concerned and in the following, nothing is done. It is clear how your flat works. Ok, while at can someone imagine while at works with match, and maybe other things.

A

Yes, youtube city doesn't interest us that there will.

B

D

A

Will hopefully, change otherwise will have in an endless loop? Yes, so she must somehow be in jubilation exactly, but everything else was correct. If you have a different opinion, someone directly in yourself introduce someone directly about writing.

A

Direct baur, a.

B

A

Broome and then also have a net in it also have climbing or the pad then applies to the torso. If that does not apply to breaking, and this break does not relate safety to the match, the person does not need a break on this loop as soon as this weather is not matched once it is. Canceled then called each other again at home. How that is related exactly.

H

A

Explosion now there is some code of some kind that can also be in a function, call that returns a random part or something else. Yes, then we do n't have to change the function call, but if this expression contains a variant such as this or something else, then so it would be pretty good if we change that on the body. Yes exactly, but it can also be at some point and on this last bankruptcy, if I have to go through it completely, there are patterns in described in their entirety.

A

Almost all of them have the syntax for what is important.

B

A

See, to introduce we have from peter that is almost a tree, for example,. The first is a dispatcher ring from a tape cheer so far had two slots, and this type 301 23 ipad on, for example, can.

B

A

Event on tour is a name, maybe the second element of tuchel that but back into the wing. That means via a wing somehow now, let's see.

D

That at some point and my.

A

Name or liter rows have arrived, good I would now go on and on.

A

I hope that you will also look maybe a little bit of English, but that the captive chapter 8, all teams who see another type of investor, see directly how it looks it. Doesn’T look like it, you might know from java or c, just have a list of possibilities yeah. Well, that's actually all up to now. So we list different possibilities on the hot rust, often like williams, and this direction can now somehow accept these four possibilities.

A

If no variable of the type director want to create, because they are complete types, also say a version live action, colon to the point, the syntax, mrd berlins and it is of the direction type.

A

If you want to see what it actually is which of these four possibilities we can think of that can west fellow human beings, we just write all four options there again with a direction in front of it. That's no different.

B

A

Example, in c or c++, high result, plus 11 or I, don't even know if ten years have passed, that all the names are not preserved. So I can't now just say north everywhere and he'll know immediately,, but you always have to address it with those with the type name beforehand,. But.

A

That's still possible in c and java that not everything we've thought of for you right away,, but you can also easily create lists. You can actually.

B

A

Bit more about things in java, but that's still a bit different life is just c and c++. You can just make lists like that from binge okay up to now, but the reason is to get the right types first. That means we can too writing in blogs so direction. This definition of straight still stays there. Now we can write any methods for this direction. For example, we can write this function.

A

That returns like the self that doesn't make much sense of this function, but it still returns, and we can also write methods that work on an instance, here. It is of the direction type and then we can use it to move people and corresponding points. Because, for example, normal functions can call normal methods and then, for example,. They cannot.

B

D

A

Any differently than best shops that what I just said, plus comes also use like strucks, also an example from the city library ordering still changes the world. What you have to do, if you implement it in java, compared to what it has to be returned, its called almost or completely or once.

E

As a big us dollars, keep others being the.

A

Larger exactly which offer returned three options, and no one.

B

Can really remember.

A

When positive numbers and negative ones say +11 is larger, but what is now.

E

D

Than others or.

B

A

Differently can now remember that, of course, for the lowest example,, something like that is given so much with the related function. And since that.

D

Is already negotiating in the city library,.

A

There is, for example, this method, reverse,, which simply turns around not a completely normal method out there. So far, so maybe still boring new lists are 409, step continue and look at what is innermost, so we can define it is what css colors should represent.

A

I don't know if you ever saw 4 ss had mackenzie it's that from the web area. Css is seen before. Ok. First of all,.

B

A

Should only a language that you can use to write the style of websites, of elements on websites and painters now specify colors,.

D

For example,, these colors.

A

Can be specified in different formats, for example,, you can simply say it is not a color,. So, of course it is somehow displayed anyway, the color from the parent next to the inherited or something else. In any case, that van stein or you can lie here like color switzerland, joked series of firmly defined color names that you can use, or you can.

D

B

A

In hesse, which.

C

We will ignore for.

A

The time being, we would now somehow like to write a css parser that left a css file there. We would like to show how a map is stored. First of all that we have the possibility, the possibilities that.

D

A

Is the same as before, there is nothing to it, but it is exciting right now. Could you add other data to it? We can say this: color is defined by a name so in the timetable. What does that help.

D

If you can say that now doesn’t help us, we.

A

B

D

A

About what kind of color it is in other languages , you would then at some point choose a different one types put it.

B

A

Into the truck, for example, and then have a string in it, the work always exists, but only has meaningful content. If this variant is chosen based loose is different. This stream is dirt and berlin attached and then we still used it to the full. Then we went after try this rgb variant, they somehow fit and say this is rgb, and here we also see terminated fields, and then we do it. We can discuss what else often ends up being said. How do you use it now?

A

You create, for example, like this, so let's create a trailer object in and say something it is carla. On the other hand, a string object in- and we can do that too, with he selected, for example at and he lets.

D

It be used somehow we have to.

A

Use that on people- and here comes this pattern again to carry the structuring now, the structured, who also writes him to the first thing, is pretty clear. First of all, it's nothing, but if we want to have this stream now and see what's up, if the name is, then we want to have the string. Somehow, it seems to me that we're allowed to write quite like that normal in berlin, then.

B

A

In this case, the red brackets a pattern. What the name of the we.

B

A

Saw don't necessarily want to take over.

B

The ownership of string, but have to go with.

A

A reference friends.

A

Just the same way for this other one here want, we are now also interested in the certainly so certain fields, assumptions. In both cases, we are only.

G

Interested in that he and.

D

A

Are g and b and so meet interested people, and here we see these are all mentioned very briefly per point would simply have to generate the other fields here you could give out here, so if your manager would do blue would be issued. So that is, yes is a name with the strict blue and if you would do match, then one will come up with that case, and there would be a reference to that name, though, if we humans b would.

B

A

This would like to go in on this last case, and 0 would be output because it is from because it is also important that, of course, these are peter riepl. So the hits don’t always come to this css caramel hits me all the time, because that will be another option too. We want to show you an example from the city library, for example,, but there are two versions of ipv4 and ipv6 addresses,.

A

That’S why it’s done in the same way in the library,, there are extra types for a 4 and 16,. These are extra, for example,. The still keeping up with 34 is easy, a raid of length 4 with 8 36, but something else- and here too a few methods are now defined, such as this is ludwig. Beck is just 100 27.1 from altenberge its properties, ip addresses.

A

It was also implemented in such a way that you can simply match the individual and then both of you have the different routes of the different types to this name, and then these types will have this ip 4 runs and a v6 interest. They also have another method, is lubek and that’s. How it’s implemented.

D

A

That’S one thing you can do with a lot of practice understands best and you have a bit of something to do with over 1 marcel l everywhere. Then I would like to say something very briefly. First of all, there were other interesting things that might make it a bad idea to do that.

A

Now that we're quite you're, probably done with all that I just said, but we're still trying to take a step back in vegas, and can you use the term meant for types theory, appropriate data types and now first want to go there and look at types as a set mathematical set a set of things to Example of finite types, such as boule. It is a set with the elements, crew and forest 32.

A

It is also a set that is finite, but much larger, that the numbers 0 1, 2, 3 and minus 1, -2 and so on, are in there up to then two billion to 2 to name billions. Do you have any idea what an infinite, what an infinite type could be just right strings can have infinite elements. This set is not a problem for us, so I mean known thats, just imagining that this set must actually make it more used.

A

Now he notices the types that are there and that are already there when we build the plant,. Of course, we are already there,. Our fields already exist and we can use these types that he can combine in different ways,.

A

For example, there is.

D

A

That has it from his point of view,: that's enough, for example,, but if you're a type of son, you're using, we'll combine the sets,. That means we take all the elements from the set and all the elements from the other set and combine the opposite to that,. There's a product type, that's ums traction tube. They form the pathetic product of the two quantities or of several lengths.

A

Example. Don't worry we have you have this order agenda from earlier, how big this quantity 3? There are three options for this. Google have just said: there are two options for and we build forest us two types of one type, because mobile phones pay. There are two billion.

B

A

This content reached a and b 1 a sticks, an order renke de buhr. We do almost the same.

B

A

Product type extract, he also two fields.

B

A

Case its ordering different and b is good, like that.

B

C

A

Through in our mails and sms, I hope the animation works. It's really cool. I just announced we have two elements of this lot, namely shoes and fords, and I do n't think for audrey survey now at all, but that you are also not aware of it, because there are three elements in it, namely leaves nicole and greater, and now it can be an interesting question which elements do I have in the set that describes the sun. That makes us all think about it.

B

A

Exactly and if we do the best one writing with others, looks like this recife lagreat and a bvs and b. These are no sum type or additive types, because the longer or the size of the amounts have their second grip, for which.

C

Possibilities which.

A

Instances are there of product product think again for a moment right away, interesting to make yourself.

E

The backdrops and kuwait just right.

A

B

You count that,. These are all combinations of these.

A

Two fields you pull through come to 6, therefore product type or multiplier type, because it is the English who, in the largest of the amount from before together multiplied the difference between 5 and 6 is not very big here, because we have very small types and if the 32 or others, so, if you have 232, then we have four billion times four billion possibilities. If we dry them in 1, every 32 4 billion, we have four billion times four billion possibilities. If we like in europe, almost four billion plus 4 billion possibilities.

A

D

A

It makes much less sense.

A

Somehow think, maybe that does n't make much sense, because you can't do anything practical, but that's interesting to look at such types and that can otherwise get started against and, for example, deal with the theory more closely, which, by the way I haven't done yet that's probably interesting. You can approach such type systems very mathematically. In any case, they are always additive type or sung types, and the products or tube ins create this despite or two pence or turbulence trucks, and also in the rest of the airways are multipliers, types or product types good.

A

There are sometimes two very, very, very important dina us that already exist in the city library that, once that china option option is defined, it's.

B

A

Again, that's genetic about this topic for two possibilities there are, and together this option represents a possible value. I already said it according to about t and we'll see what to.

B

A

That's initiate everything else. Okay, we ask ourselves. Maybe why is that necessary? I was supposed to object to a web before then in rast. There isn't one, for example. What I have I noticed that, but let's not references always have a valid value. What does it.

D

A

What for now so an optional value, a value that might be because it might not be a good example of this, the app is there a function or method that should get the value out of the app for a specific key, but of course, there isn't one for every possible one key, also a wave hefner it works, for example,. That means this method will already return a place if it value could.

B

Be there or could not be there.

A

In java, you might return close, maybe throw an exception here. You return that as an option. We use also always want to say my. There is possibly a value there, but it could also be that it is not from. I said just now: there is no shop rust. Everything is always all references and always valid and cannot be a normal value as orphans, and you have to.

A

Mark all things,, I.e. all possible absences of valid values,, and you have to explicitly mark them with this optional, by the way,. The inventor friend also called the half a million dollar mistake because no, it’s extremely dangerous. It caused so much damage that everything can be new I’ll. Do it not quite into detail but well, because it is so that everything can always be close. It doesn't have to be somehow a value I as the productive data type, but it can always be that the value existed.

A

The organ relieved, and maybe it exists now slowly more. What I mean by that is the feeling of being able to write robust applications in java, whitish.

B

That even then.

A

There is no behind it in the year. I can't know what do I know that whenever any function returns a value or a string without an option drum rum, then I know that there was always a valid instance of this type back, but.

B

A

That so, if you are more interested in that the million dollar mistake, kadima google described it to me again nicely what everything is wrong. That's just bad to incorporate into a language, but it's so easy. That's why many spoke then you shortened it so result. Result is a bit expanded from option to. Should you tell me my pace, pace or variant that just presents a calculation or something else that can go wrong so almost the same as options only that we have more information about the error.

A

It's about tnt generic two types march, but I hope that doesn't bother us my understanding.

A

So if we take the example of mr schmidt again, so to speak, the hunters, but we notice it back why no valid value can be returned. Mr schmidt, is there another idea why this value is not in the first one, but I have another example. She says, because the photos almost stretch and change it to another type, and this case was.

C

D

C

A

Pasing of string can go wrong. Obviously, if you now say hello in it, it can't fit as an integer. These parts method return the be to old. In this case, the.

D

Passwords can say even.

B

A

Precisely what went wrong somehow I now have a good example from there can still say exactly is a place in the sting is somehow that divides that doesn't belong to his meter. So more information comes back here by the way here that 's a ration also partly can't write. If it's not quite finished this underscore, you could.

D

A

Result what now a reset has happened? We can also go back to people in the ok value. We don't do anything or use this value in the event of an inheritance. We find the award,, for example, more about this in the chapter experience so that you look better finally came to the conclusion that you can look at it again in detail. Take a quick look at the exercises. I uploaded them again quite late yesterday.

A

These are two exercises. The second one is a bit bigger. It's about you getting used to a somewhat larger coface. There is probably already a lot in it where many people are afraid of a valve of the truck, and there are a few more things added or the main function contains builds in, and this task is also welcome to ask piazza that has deliberately become a bit better. This task, then, have fun with the tasks during the test drives.