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Avoiding the quote problem

Because this is such a common problem, and because the escape solution is so ugly and difficult to read, Python gives us another way to deal withquotes inside of quotes. This solution, shown in Figure 6 , is the use of single and double quotes in combination.

Figure 6 . Avoiding the quote problem.
>>>print('Richard "Dick" Baldwin') Richard "Dick" Baldwin>>>

In Python, double quotes can be included directly in strings that are surrounded by single quotes, and single quotes can be included directly instrings that are surrounded by double quotes. This is much easier to read than the solution that requires you to place a lot of backslash characters insideyour string.

List of escape sequences

Escape sequences are a staple of modern computer programming and there is a lot of consistency from one language to the next. A list of the escape sequencesthat are honored by Python 3 is available in the Python Language Reference -- 2.4.1. String and Bytes literals .

More ways to span lines

Just when you thought that you had seen it all, I am going to show you three more ways (two new and one not so new) to span multiple lines with strings. One of them is shown in Figure 7 .

End the line with a backslash

Figure 7 . End the line with a backslash.
>>>print("Richard \ Baldwin")Richard Baldwin>>>

As shown in Figure 7 , the use of a backslash at the end of the line makes it possible to continue the string on anew line. However, the backslash is not included in the output, and there is no newline character in the output.

Not restricted to strings

The backslash can be used at the end of a line to cause that line to be continued on the next line whether inside a string or not. This isillustrated in the review module following this module.

A form of concatenation

When used in this way with a string, the backslash at the end of the line becomes a form of string concatenation. The portions of the strings on each ofthe input lines are concatenated to produce a single line containing both parts of the string in the output.

I will have more to say about string concatenation later in this module.

Use the \n escape sequence

This isn't really new, but it so important that I decided to repeat it here for emphasis. As shown in Figure 8 , the inclusion of "\n" inside the string caused the cursor to advance to a new line following my first name and printedmy last name on the new line.

Figure 8 . Use the \n escape sequence.
>>>print("Richard \nBaldwin") RichardBaldwin>>>

This is the common form of the newline escape sequence typically used in C, C++, and Java.

Combine backslash and \n

The code in Figure 9 shows how to combine the backslash at the end of the line with a newline character placedthere to cause the output to closely resemble the input.

Figure 9 . Combine backslash and \n.
>>>print("Richard \n\ Baldwin")Richard Baldwin>>>

String concatenation

To concatenate two strings means to hook them together end-to-end, thus producing a new string that is the combination of the two.

Literal string concatenation

You can cause literal strings to be concatenated just by writing one adjacent to the other as shown in Figure 10 .

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Source:  OpenStax, Itse 1359 introduction to scripting languages: python. OpenStax CNX. Jan 22, 2016 Download for free at https://legacy.cnx.org/content/col11713/1.32
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