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7:43Let's wrap up this application and review it in its entirety.
Okay, first thing's first, I'm gonna wipe
our all these instructional columns.
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Let's get rid of all of these,
clean that up a bit.
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Let's get a little noisy.
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All right, awesome.
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So, that feels better.
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Let's look at what we have left.
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All right so we left done here because
we want to print the list out in
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totality when it's done.
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We wanna show the list and
there's this one here too.
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I wanna see the list any time so
I can verify my order.
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So let's make a new command for that.
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That sounds good, all right?
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So let's come back over here.
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So first,
I'm gonna clean this up a little bit.
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I'm gonna move this add to list
down below the show help and
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typically what happens
in between functions,
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you'll see that the starts getting
busy is you leave two spaces.
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So there we, so we left that two
spaces between the two there.
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Before and after, there you go.
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All right, so we want to define a new
function that's named show list.
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So let's do that.
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So we'll say, define a function
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named show_list that prints
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all the items in the list.
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That sounds good, right?
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You got this, right?
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You can loop through all of them and
print them out, right?
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You got this, ready?
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Pause me.
How did it go?
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Here's how I did it.
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So I said def show list.
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Here's your list,
nice little heading there for it.
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And we're gonna loop through that list.
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So for each of the items In the shopping
list, we are going to print said item.
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Awesome, and now,
we want to be able to have this called.
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So let's make the command SHOW,
in all upper case.
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So let's put it right here.
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We'll say Enable the SHOW command,
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cuz we wanna call that function
SHOW command to show the list.
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Don't forget to update
the help documentation.
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This is super important.
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Sometimes you'll add a new command and
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you'll forget that you've
already made this help.
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And we have the help at the top of
the file, so don't forget to do that and
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I wanna drop a hint here for you.
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Make sure to run it.
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Make sure that you run this
after you had that show command.
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There's a little gotcha
if you forget something.
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So make sure you run it, and
just make sure your list looks right.
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Are you ready?
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Pause me.
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Did you catch it?
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Here's what I did.
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So I went ahead and it's another else if.
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And if this is equal to our command
of show, we call the function.
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But we got to remember to
use our control flow, right?
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We gotta call continue and
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if not, what will happen is show
will end up in your grocery list.
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When you embrace flow control
like break and continue,
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it's super important that you pay
attention to all the used cases.
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All right, we are so close to done.
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Now, we need to show
the list on completion.
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So what we can do is when this while
loop is over while this while true when
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this is over.
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We can just call it.
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We will call show_list.
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Awesome let's give that a run.
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Let's say, Python shopping list.
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Look what I forgot to do.
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I didn't update the help,
so I don't know about show.
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I'm gonna do that.
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Let me get back up in there.
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Let's go back up in here.
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So we'll add enter SHOW
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to see your current list.
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Awesome, whew that was close.
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Okay so
we're gonna run Python shopping_list.py.
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There's the show which
we pick up at the store.
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Well obviously we need some tortillas.
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Let's get some green chiles.
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I need pork shoulder.
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What am I forgetting?
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What's on my list again?
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What do I have here?
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Right, tortillas, green chiles,
pork shoulders, cilantro.
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There we go and now I am DONE.
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And check it out there is my final list,
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you're totally invited to my taco fiesta,
look at this.
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We are all done, awesome.
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Should we walk it one more time?
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Let's do that.
So I'm gonna come in here.
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I'm gonna get rid of these instructional
commands that we have in here.
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Let's just walk it.
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So we create our brand new list that
the program will use in a global fashion.
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And then our program is gonna
accept multiple commands.
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So we should have some detailed help,
right?
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Programs are no good if
users can't use them.
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So we print out our help, and
then we have our add to list function.
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And it appends a value to
the end of our shopping list and
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updates the user with the count.
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And lists and most objects for
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that matter can make use of
the len command, so pythonic.
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And then we have our show list,
and lists are iterable,
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so we can loop through them
with a for item in list.
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Now, this is kind of strange, right?
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So we have this while True.
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One way to write loop that take
many flows is to set things up
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in an infinite loop matter.
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While true is always gonna happen,
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we rely on further control flow
to control how things happen.
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We take a single prompt and
since it can be an item or
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a command,
we have made the prompt generic.
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A little greater than sign,
feels kinda good.
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And then we just check
each of our commands.
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So here's the flow if the user is done.
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Break out of the while loop,
we are done with this while loop,
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we don't anything more to do so
break out of it.
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Otherwise if we're looking for help,
show it and remember to control the flow.
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Calling continue will shoot us back up to
this while true line which is no surprise,
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still true.
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What this avoids is us from continuing and
adding help to our grocery list.
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We don't want that.
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Well, at least not from the grocery store.
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Now, I of course, could have just put this
add to list inside of an else and we could
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remove the continues, but then I would've
been able to show you the continue loop.
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So I want you to be cautious of
controlling the flow with break and
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continue.
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Break is known to break your program,
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and then finally we add that
new item to our function.
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It comes into the add to list then boom,
here we go.
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So I hope that that all made sense, and
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if there is anything at all that is still
confusing you, feel free, rewind it,
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watch it again and hit the forum if
there's anything confusing at all.
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You did an awesome job,
enjoy the taco party.
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