Ruby Programming Tutorial - 12 - More About Variables & Methods! Video Lecture | Introduction to Coding with Ruby - Back-End Programming

alright guys welcome to your 12th Ruby
tutorial and in this lesson I want to
talk to you guys more about methods and
some more things about variables so the
first thing that I want to teach you
guys is this you know how I said that
any time you want to make a method you
pretty much make a class and then you
put your methods and attributes inside
that class
well that's true you can make them that
way we can also make methods that don't
belong to any class let me go ahead and
give you an example so you first open up
our interactive Ruby now you don't have
any classes created yet and I'm going to
go ahead and make a method called crap
or something classy like that now my
methods job is just to print something
out on the screen
something you know very formal like I am
a crappy crap crap exclamation point and
I'm just going to go ahead and end the
method now our method returns nil which
pretty much means no errors you created
a successful method now remember last
time whenever we created a class I told
you guys that you need to make an object
to access the things inside the class
and then with your object you can go
ahead and call those methods well the
thing is this method doesn't belong to
any class so how do we access it in
other words how do we use it formally
how do we call it calling it's pretty
much the same thing as using but that's
what programmers say using methods so in
order to call this method the only thing
we need to do is type the name of the
method simple enough go ahead and hit
enter and it says I am a crappy crap
crap see I am so unprofessional and
that's why a lot of schools don't use my
tutorials because I'm just incredibly
immature so I just want to mention that
anytime you want to make a method that
doesn't belong to any class that's how
you create it and that's how you call it
just by typing the name of the method
now before I let you guys go I want to
talk to you guys a little bit more about
variables specifically naming variables
now I already told you guys that you can
make a variable by giving a variable
name such as beans and setting it equal
to a value like 20 my favorite number
but you just can't name it anything you
want there are a couple conventions on
how to name variable
first of all you can't have spaces you
can't have something like a doghouse
equals 14 it has to be all one string
basically no spaces or anything like
that so just remember that another thing
is it must start with a letter or an
underscore so for example beans would be
good or underscore Bucky but something
like 3x this doesn't start with a letter
or an underscore 3x starts with a number
so if you try to make a variable called
3x and set equal to 5 you're going to
get an error
whenever you do this as well another
thing is your variable name must only
contain letters numbers and underscores
so you can't have something like Bucky
and then a bunch of weird symbols and
set it equal to 99 or 999 you're going
to get an error because like I said this
dollar sign % caret ampersand those are
symbols and you can't have those in the
variable name
another thing is variables are case
sensitive so for example if you have B
and you said equal to 5 and you have
uppercase B and you said equal to I
don't know like 64 whenever you type B
lowercase B is equal to 5 and uppercase
B is equal to 64 two different variable
names lowercase and uppercase two
different values so just remember that
so before I start going into more about
variables and expressions and how you
can assign the value of variables to
other variables I'm going to let you
guys soak in this knowledge so for now
thank you guys for watching don't forget
subscribe and I'll see you guys in the
next video