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I like to imagine string just like a
banner you might see at a party with each

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letter strung together.

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That's really what a string is, right?

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It's a series of characters.

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The string data type provides some very
handy methods that I'd like you to get

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familiar with.

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After you create a string,
it cannot be changed.

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This is what is known as immutable or
impossible to modify.

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I'll remind you of this as we
look at some of these examples.

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Why don't we pop open a shell and
I can show you what I'm talking about.

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So, string literals, they can be made
with either single or double quotes.

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And I can imagine that you
might say something like this.

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You could say, 'I cannot understand
why you need two options for quotes'.

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Totally understand why you
might say something like that.

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But that's probably a little bit formal,
isn't it?

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We should probably use a conjunction.

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How about we say something like,
'I can't understand'.

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Oops, that's a problem, right?

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We've got a quote inside of the quote.

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We got a single quote, we are trying
to use a single quote, uh-oh.

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Now, option is that you
can actually make it so

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the quote is ignored by doing
something called escaping.

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So the backslash starts what is
known us an escape sequence.

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So the backslash, and

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then a quote, basically tells
the interpreter to treat that quote

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like a character instead of treating
it like part of the syntax, right?

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So if I do, can\ 't understand,
now it will see.

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But, I mean this is kinda ugly, isn't it?

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This backslash t.

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Are you glad there's two
types of quotes yet?

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And actually, look, the REPL fixed it.

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So you can use quotes like that.

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So if you use double quotes,

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then you could very easily use
the single quote inside of it, like so.

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Now we can say, "I can't", right?

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There's a nice string.

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And actually,
escape sequences are great for

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adding blank lines inside of your string.

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So there's a special one that you'll see.

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If we come over here and we go up,
let's get this I can't back here.

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Let's say "I can't..., and
then we wanna add a new line.

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And so that escape sequence to add
a new blank line is \n for new line.

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So we'd add two, two blank lines and
we'll say, I can't even.

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And the REPL here is playing tricks on us.

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It's trying really hard to keep
things on one line for us.

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But actually if you print that string; so
we'll go ahead and say we'll print.

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And then we'll get back the result
that was just there, right?

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So we use the underscore.

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So you'll see that it is actually
I can't new line new line even.

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There's our new lines.

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My wife says that to me all the time while
shaking her head about my dad jokes.

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You're not the only one.

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I suppose,
I should quote her though, right?

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So I would say, "She said,.

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[LAUGH] I can't, so now what?

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Now we've got a single quote and
a double quote in here.

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So actually, triple quotes
allow you to start the string.

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So we could say, """She said, "I can't...

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And the nice thing about triple
quotes is it allows you to have

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spaces in your string.

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So we can press like this and
see those triple dots over here.

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That means, it's waiting for me to,
it's waiting for those final three quotes.

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So we can say, "I can't...

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even.", so she said that.

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And still,
there's another quote there, right?

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So I'm ending that quote and then it's
waiting for three quotes to end it.

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So there we go, and if I say, go up
a couple times here, we say, print (_).

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She said "I can't...

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even.", that's what she said.

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All right, so
now that we got creation out of the way,

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let's look at combining
some strings together.

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What if I had a string like this word,
here, chocolate?

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Now we can actually combine it together
with another string using a plus sign.

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So I can say, "chocolate" + "marshmallow".

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And you'll see what it
returned was a brand new

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string with the two words pushed together.

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This is called concatenation.

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Now, it's important to remember when
you're concatenating strings to include

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the proper spacing.

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Otherwise, it will be
slammed together like this.

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So what we want is
probably more like this,

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"chocolate' + " and

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marshmallows".

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There we go, that feels good.

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And of course,
we can store that new string that

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was created in a variable, right?

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So, we could say desert =
"chocolate" + " and marshmallows".

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So that was a new string created and
then we labeled it with dessert.

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And we can use that variable
to create a brand new one.

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This is called reassigning.

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So as I dessert = dessert + " and
graham crackers".

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And now, that might look like
we changed the variable dessert.

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But what happened was that this statement,
dessert + " and

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graham crackers", created a new string.

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And we removed our already existing
label and put it on the new string.

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We reassigned it.

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The old string,
since it didn't have a label,

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is essentially thrown away,
like those leftovers in my office fridge.

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Remember, we didn't actually change the
original string because we can't, right?

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And that's because strings are immutable.

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This appending of more text to
the end of a string is pretty common.

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So there is a shortcut
called in-place addition.

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So if we say dessert, we can say +=.

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And basically,
that's just like the line above.

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It's saying dessert = dessert + and
then whatever we do.

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So we say += ", yum.

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And if we take a look, 'chocolate and
marshmallows and graham crackers, yum'.

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So [LAUGH] that needs some
exclamation points, am I right?

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And I want some more than just a couple.

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I don't wanna just add
a whole bunch of them myself.

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I'd rather do that in code.

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So that's where the asterisk
comes into play.

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So check this out.

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If I want to repeat the string, well,

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here's the string,
I can then do a * for multiplication.

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I say do that 20 times.

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Awesome.

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In addition to exclamations,
this is really handy for

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trying to draw layouts in text.

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So let's append those.

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So we'll say dessert, and
we'll do an in-place addition, so dessert,

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basically, that's desert +=,
and we'll say "!" * 20.

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And there we go.

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Now before I append some more
string information in your brain,

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let's take a quick break and
return to talk some more about strings.

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We'll talk about various handy
methods that a string provides.