How can I do a line break (line continuation) in Kotlin

syntax kotlin line-breaks long-lines
bryant1410 picture bryant1410 · May 25, 2017 · Viewed 19.1k times · Source

I have a long line of code that I want to break up among multiple lines. What do I use and what is the syntax?

For example, adding a bunch of strings:

val text = "This " + "is " + "a " + "long " + "long " + "line"

Answer

bryant1410 picture bryant1410 · May 25, 2017

There is no symbol for line continuation in Kotlin. As its grammar allows spaces between almost all symbols, you can just break the statement:

val text = "This " + "is " + "a " +
        "long " + "long " + "line"

However, if the first line of the statement is a valid statement, it won't work:

val text = "This " + "is " + "a "
        + "long " + "long " + "line" // syntax error

To avoid such issues when breaking long statements across multiple lines you can use parentheses:

val text = ("This " + "is " + "a "
        + "long " + "long " + "line") // no syntax error

For more information, see Kotlin Grammar.

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