1 00:00:00,840 --> 00:00:05,550 Welcome to lesson 21 in this short lesson we'll talk about string formatting. 2 00:00:05,550 --> 00:00:10,320 Normally when you want to combine strings together to form a single string value you can use the plus 3 00:00:10,320 --> 00:00:13,030 operator to concatenate strings together. 4 00:00:13,380 --> 00:00:21,490 For example you can have a blue plus the string world and that evaluates to the single string value 5 00:00:21,630 --> 00:00:23,060 Hello world. 6 00:00:23,130 --> 00:00:28,770 This can get tricky if you have several strings that you need to concatenate create several variables 7 00:00:28,790 --> 00:00:28,910 . 8 00:00:29,010 --> 00:00:38,710 Let's have name equals the string Alice This place is Main Street Time is the string 18:00. 9 00:00:38,940 --> 00:00:41,870 Food is the string turnips. 10 00:00:42,210 --> 00:00:47,520 And then we have a large string that we want to concatenate all of these together with it look like 11 00:00:48,060 --> 00:01:00,750 a simple invitation so we can have hello plus name plus you are invited to a party hat and then we'll 12 00:01:00,750 --> 00:01:10,260 concatenate the place variable then add at plus time plus period. 13 00:01:10,260 --> 00:01:12,860 Please bring. 14 00:01:13,350 --> 00:01:19,850 Then plus food and then plus for that final period that evaluates to. 15 00:01:19,860 --> 00:01:20,820 Hello Alice. 16 00:01:20,820 --> 00:01:23,900 Alice you are invited to a party at Main Street at 6pm. 17 00:01:23,940 --> 00:01:25,440 Please bring turnips. 18 00:01:25,440 --> 00:01:27,310 Sounds like a great party huh. 19 00:01:27,690 --> 00:01:33,680 Anyway this expression right here looks really complicated we had to take a lot of quotes allow pluss 20 00:01:33,680 --> 00:01:34,370 . 21 00:01:34,470 --> 00:01:38,940 It's kind of hard to read as well so pile on has something called string formatting. 22 00:01:38,940 --> 00:01:40,820 It's also called String interpellation. 23 00:01:40,980 --> 00:01:48,270 And this lets us put a percent s inside of a string to mark where we want to have other strings inserted 24 00:01:48,270 --> 00:01:49,160 into it. 25 00:01:49,350 --> 00:01:50,440 I'll show you what I mean. 26 00:01:50,730 --> 00:01:57,630 So we can have this exact same expression typed out like this hello and then instead of this end quote 27 00:01:57,660 --> 00:02:03,810 plus name plus and then another quote We can just have percent S and we can type out the rest of the 28 00:02:03,810 --> 00:02:04,360 string. 29 00:02:04,550 --> 00:02:09,460 You are invited to a party that percent s percent. 30 00:02:09,520 --> 00:02:12,410 Yes please bring. 31 00:02:12,610 --> 00:02:13,090 Percent. 32 00:02:13,120 --> 00:02:13,770 Yes. 33 00:02:13,900 --> 00:02:15,140 And then period. 34 00:02:15,600 --> 00:02:21,750 And then after that string we can have a percent sign followed by parentheses. 35 00:02:21,780 --> 00:02:26,850 And inside the parentheses will have a comma delimited list of variables that we want to have inserted 36 00:02:27,150 --> 00:02:28,580 at these percent S's. 37 00:02:28,650 --> 00:02:31,730 These percent S's are called conversion specifiers. 38 00:02:31,770 --> 00:02:41,100 So you can have the string in name be assigned or be inserted at the first percent S and then we can 39 00:02:41,320 --> 00:02:45,050 place time and food. 40 00:02:45,570 --> 00:02:51,390 And this evaluates to the exact same thing that this huge string concatenation expression evaluate to 41 00:02:51,560 --> 00:02:55,090 Helliwell as you're invited to a party at Main Street at 6. 42 00:02:55,110 --> 00:02:56,670 Please bring turnips. 43 00:02:56,850 --> 00:03:03,570 Now this string is a lot easier to read and we can put all of the strings that we want to insert side 44 00:03:03,570 --> 00:03:04,740 of it at the end. 45 00:03:04,740 --> 00:03:05,260 After this. 46 00:03:05,300 --> 00:03:11,940 Percent and then have it inside parentheses by using string formatting you can make your code a lot 47 00:03:11,940 --> 00:03:12,870 more readable.