Question

While using IntelliJ Idea to code Scala I’ve noticed it to use to offer to enclose a string literal in a second pair of double quotes. «Convert to “””string”””» – it says. If I agree – it just adds a 2 more double quote marks before and 2 more after the string, having my string to look like

val myString = """my string value"""

How does this make any sense? Do triple double quotes mean something special in Scala?

Answer 1

With IntelliJ smart String, there should be only two cases.

• simple string (which you can convert to triple double-quotes multi-line String literal)
• multi-line String literal, introduced way back in Scala 2.1.7 (which you can convert back to a single String)

So when you see this:

you should end up with """. If not, this should be reported as a bug in the youtrack Scala project.

---

But if there were triple double quotes, then IntelliJ correctly transformed your simple String into a multi-line String literal, which, as illustrated by langref, allows you to define:

val text = "This\nIs\nA\nMultiline\nString"

into

val text = """This
Is
A
Multiline
String"""

Rosetta code mentions the behavior has changed between Scala 2.7 and 2.8:

on version 2.7, the triple-double-quoted string ends at the third consecutive quote, on version 2.8 it ends on the last quote of a series of at least three double-quotes.

Scala 2.7:

scala> val error = """can't finish with a quote: """"
<console>:1: error: unterminated string
       val error = """can't finish with a quote: """"
                                                    ^

Scala 2.8

scala> val success = """but it can on 2.8: """"
success: java.lang.String = but it can on 2.8: "