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Alright so in this video we're
going to talk about classes so
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I'm going to show you how to
type a class and you're going
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to notice that it's actually
pretty straight forward if you
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already know how to type
functions we're going to create
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a new class that is going to be
a vehicle like this in this
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vehicle we will have two
variables, will have the speed
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that is going to be a number
and a brand that is going to be
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a string the we're going to
create a constructor to be able
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to send values to our vehicle
so constructor like this and we
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are going to receive a speed
that is going to be a number
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and a brand that is going to be
a string and then we are going
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to fill our variables with the
values that we have here so I'm
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going to do this speed receive
speed, and same with the brand.
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Now I can create my first
vehicle so let's say I have a
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Honda here that is going to be
a new vehicle and I'm going to
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send my speed and my brand so
for example 200 my brand is
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going to be Honda like this now
I can log my own data so for
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example I can log my brand like
this and as you can see no
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problem with that, now if I want,
nothing prevent me from
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updating the content of my
class directly from here, so I
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could do on the dot brand
receive something else for
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example Tesla but this is
pretty dangerous okay because
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now if I log it for example Honda dot
brand as you can see
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it's been updated and maybe I
want to make sure that when my
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brand is updated I want to make
sure that it has a correct case
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okay it start with an upper
case and the rest is in lower
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case for example but maybe I
want to make sure that when I
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send a brand it has to be in
pascal case for example like this okay
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with an upper case at the
beginning so by doing that I'm
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not able to do any check so
what I would do is I would
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create for example a set brand
to manage myself how I update
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the brand right so I would
receive a brand that would be a
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string and this would return
absolutely nothing okay so I
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would set void and I would just
take my brand and send inside
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the new brand so I'm going to
call that new brand the new
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brand I'm just going to take
the first character and put it
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in upper case and I'm going to
add the rest of the word in
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lowercase so I'm going to use
new brand dot slice and I'm
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going to slice I'm not going to
take the first character only
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the second one and I'm going to
go until the end of the word so
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new brand. lens I'm going to
put that in lowercase like
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this. So now instead of doing
that what I could do is on
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that. said brand and send for
example Tesla and yup, it's
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correctly formatted but I'm
still able to do that so I
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could for example say that
specifically I want this to be
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read only and now I cannot
write anymore in my vehicle
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from here okay but you're going
to notice that I'm also
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affected here okay I cannot
update my brand anymore because
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this is read only so this is
problematic because I want to
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be able to modify my brand from
my class but not from outside.
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Okay? So this is problematic.
So as you can see obviously
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it's still working okay here
but as a developer I know that
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there is an error here, okay? I
shouldn't be doing that. So in
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the next day we're going to see
the different access level that
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you can set on a variable. So
private, public, maybe you have
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heard already of this accessor.
So we're going to see that in
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the next video to be able to
have different level of
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privilege inside a class and
outside. Okay? So see you on
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the next one.