Strings

Quick reference

• 00:04 In this video, I want to talk about strings in a little bit more detail.
• 00:08 And so let's create a string.
• 00:09 Let's just call it my_string.
• 00:11 This is a terrible name for a string but it will work for us here.
• 00:14 So, I've mentioned in the past that strings can be
• 00:17 inside these double quotation marks or single quotation marks.
• 00:20 But we haven't actually talked about what the difference between the two is, or
• 00:24 why you might want to use one set over another.
• 00:27 And that's what I want to talk about right now.
• 00:29 So as we know, we can print this out just by going, my_string.
• 00:34 So let's say we had a string and let's say inside here, we said, we typed in,
• 00:39 The teacher said, "PAY ATTENTION!" and
• 00:44 we wanted this "PAY ATTENTION!" to be printed out inside quotation marks.
• 00:48 Well, if we do it like this, if we run this, we're going to get an error,
• 00:53 you can see.
• 00:53 Because what's going on here is, we're starting with the quotation mark, and
• 00:57 Python is looking for everything inside of these quotation marks and
• 01:01 when it sees the next set of quotation marks, it stops.
• 01:03 And then everything after here, it doesn't know what to do with it,
• 01:07 because it thinks that this is the string and then it's just confused.
• 01:11 So in this case, you might want to wrap your string in single quotation marks.
• 01:17 So when you use single quotation marks as the outer wrapping,
• 01:21 you can use double quotation marks inside.
• 01:23 And see now, Python says okay, we're starting with a single quote.
• 01:26 I'm going to keep looking until I find the next single quote.
• 01:29 It goes all the way to the end.
• 01:30 It ignores those two double quotes and it sees the single quote.
• 01:34 So now if we save this, we can run it and it says, The teacher said,
• 01:38 "PAY ATTENTION!".
• 01:39 And the PAY ATTENTION! is in nice quotation marks.
• 01:42 Likewise, we can reverse this as well.
• 01:44 We can put the double quotes on the outside and
• 01:47 the single quotes on the inside.
• 01:52 Just like that, if we save this, we're going to get the same exact thing,
• 01:55 teacher says 'PAY ATTENTION!', only now, it has these single quotes on the inside.
• 01:59 So, that's really sort of the main reason why you're going to choose single over
• 02:04 double, or vice versa.
• 02:05 It's if you're inside of here using these things.
• 02:08 Now, there's another way you could do it as well.
• 02:10 If we want double quotes on the outside and the inside,
• 02:13 we can use something called an escape character.
• 02:15 And that's just the backslash.
• 02:17 And you can see, once we do that,
• 02:18 this quotation mark turns blue and we need to do another one right there.
• 02:22 What this is doing is it's escaping out.
• 02:24 It's saying okay, the next character you see, just ignore it.
• 02:27 Just print it out, don't run it as a string type thing,
• 02:30 just kind of print it out as text.
• 02:32 So if we save this and
• 02:33 run it, now it works again because of the escape characters.
• 02:37 So we can use double quotes inside and outside and the same thing holds true for
• 02:41 the single quotes as well.
• 02:42 So that's an escape character.
• 02:43 There is also another kind of neat thing you can do with an escape character.
• 02:47 You can do n, n stands for new line,
• 02:50 so if you want, you see, this is all on one line.
• 02:53 In fact we could come back here and we could say \n.
• 02:58 We save this and run it, the teacher said PAY ATTENTION! and
• 03:02 it's put this PAY ATTENTION! on a new line.
• 03:05 So that \n stands for.
• 03:07 So escape character, new line and single quotes, double quotes.
• 03:11 Really those are the main things you want to learn about strings.
• 03:14 So you're going to use strings just all the time.
• 03:17 I mean, they're like the most fundamental building block of any
• 03:20 programming language, and Python is no different.
• 03:21 So get good and used to creating your own strings.
• 03:24 Use double quotes or single quotes.
• 03:26 A lot of the time it's just a matter of style.
• 03:28 You might always use double quotes or you might always use single quotes.
• 03:32 Sometimes like we've seen in this video, you'll need to use single or
• 03:36 double quotes, but for the most part you just use whichever feels right to you.
• 03:40 Personally, I use double quotes, just because I do.
• 03:43 But like I said, it's really just a matter of style.
• 03:45 So in the next video, we're going to look at string manipulation.

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