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Multiline string literal tips

In Swift, we can use multiline string literal to express several lines of string. Although, adding the new line character \n can create line break, it only works for string that are displayed. Use multitline strings for formatting string nicely.

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let quotation = """
We can make multi-line strings.
Use three double quotation marks.
Also, multi-line strings can write "quote marks"
"""


When using multiline string, always start and end the content using """ on single line.

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let badMultilineString = """This will not create multi-line string.
Always start with an new line and end before a new line."""

let goodMultilineString = """
This will create multi-line string.
Always start with an new line and end before a new line.
"""


We can also add backslash \ for reading a very long string a bit easier. This will not change the value.

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let veryLongString = """
Lorem Ipsum is simply dummy text of the printing and typesetting industry.
Lorem Ipsum has been the industry's standard dummy text ever \
since the 1500s, when an unknown printer took a galley of \
type and scrambled it to make a type specimen book.
"""


We can indent strings in multiline string. The indent will start at the closing quotation marks """, before will be ignored. So in the following code, the second string will have indents.

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let linesWithIndent = """
    This line doesn't have indents.
        This line has indents.
    This line also doesn't have indents.
    """


When building a longer strings with multiline string literals, every line in the string needs to end with a line break.

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let badStart = """
one
two
"""
let end = """
three
"""
print(badStart + end)
// Prints two lines:
// one
// twothree

let goodStart = """
one
two

"""
print(goodStart + end)
// Prints three lines:
// one
// two
// three
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