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Okay so now we're going to work
on the favorite accounts
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feature so technically it seems
that it's just a regular array
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of accounts okay we can access
the list of the favorite
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accounts we can add an account
into the list and we can remove
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an account to the list by it's ID
that's the only one where we're
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going to need a little bit more
logic but otherwise it's just a
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regular accounts array right so
let's go into our project and
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let's create now a favorite accounts
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and it's going to be a bank
account array, so we should have a
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function to be able to add
something into it so I'm going
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to add account to favorites
and we're going to receive a bank
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account.
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And so simply so this is not
going to return anything it's
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just going to perform an
operation and here we're just
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going to push this account into
the list so this.favorite
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accounts.push account and
we're good we should have
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something to return the
favorite accounts so I'm going
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to create a get favorites
accounts so this is going to
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return an array of bank account
so bank account array like this
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and we don't expect any
parameters because we're going
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to use only what we have in our
class and we're just going to
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return this.favorite
accounts so we can try to see
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if we can add an account and
get the favorite accounts but
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we're going to have a problem
because we have never
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initialized the bank accounts
here, okay? Uh we have to set a
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default value so we should put
anempty array here. Otherwise, you
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won't be able to push inside
and we'll have an error. So
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this way it's going to be
initialized. Now we could just
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test it. So technically I can
just do an account one dot
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Add account favorites I'm just
going to create a new account
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so account two
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I'm going to Create another
one.
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Like this and I'm going to add
this account to its favorites.
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And technically I should be
able to see this account if I
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do a get favorite accounts and
take the first one for example
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and look at the balance it
should be 100000 so let's see
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Okay, it's working fine. So
we're good with accessing the
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favorite accounts, we're good
with adding an account, but now
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we have to remove an account
from the list by its ID,
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meaning that an account should
have an ID, which is not the
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case yet. So we are going to
create an ID that is going to
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be a number. And we're going to
receive this ID okay so we will
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assume that it's not generated
but sent through the
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constructor so I'm going to add
an ID that is going to be a
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number maybe I can put that on
first parameter like this okay
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we're going to receive this ID
from the constructor good so
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now technically here this could
be the ID1 and this could be
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the ID2 and I need to create a
function to remove an account
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from the favorite list by its
ID so we're going to create a
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remove account by ID remove
favorite account by ID and
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we're going to receive an ID
and this is not going to return
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anything it's just going to
perform an operation so in the
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end what we're going to do is
we're going to look at the
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favorite accounts and just
remove one element so we're
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going to use the function
splice and and with splice
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basically you can say that you
want to remove exactly one
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element and here you're going
to say starting from where from
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which index so we need the
index to remove this one
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element so we're going to use
the find by index so we're
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going to take the favorite
accounts and find by index and
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here you can send a function so
here we're going to run a
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function for every element so
this is an account so bank
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account and here we are going
to return the index of the
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element that match this very
predicate here that we're going
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to write so something that
returns true or false and we're
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going to say that if this
account
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in my list is equal equal to
the ID that I have sent here
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then I want to return this
element and it's going to
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return me the index so I will
have here the index to Remove.
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And then I can just send this
here but be careful if the
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element is not found this is
going to return minus one so we
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have to check that if this is
equal to minus one that's then
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we're going to throw an error
throw new error account not
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found in favorites and we
should be good so now we could
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just try to test it quickly So
we have the ID2 into our list.
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So I'm going to remove that and
I'm just going to do an account
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one dot remove favorite account
by ID I'm going to remove the
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ID2 and then print account one.get
favorite accounts.length
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technically should be zero
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Yep, it is, okay, fine. And now
if I try to remove again this,
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this should trigger an error.
Yep, okay, it's crashing,
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perfect. Okay, so we're good
with the specification. Now in
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the next video we're just going
to work on the story. So let's
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do that in the next one.