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New blog post about Kotlin's multiline strings
author Dirk Olmes <dirk.olmes@codedo.de>
date Fri, 12 Jun 2020 12:56:06 +0200
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1 Title: Kotlin multiline strings vs the $ character
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2 Date: 2020-06-12
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3 Lang: en
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5 I recently started to use [Kotlin](https://kotlinlang.org/) for small projects at work. At first I was very pleased with the language but the more I use it the more I'm stubling over things that are not nice.
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7 I'll rumble about the braindead constructor syntax or the epic autoboxing fail with numbers some other time. Today I'll get into [multiline string templates](https://kotlinlang.org/docs/reference/basic-types.html#string-templates) and the use of the `$` character.
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9 Kotlin, much like [Groovy](https://groovy-lang.org/) supports multiline strings. It also allows the use of `$`-epxressions in the string. Things start to become difficult if you need a literal dollar sign in the string.
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11 Embedding literal dollar signs in Groovy multiline strings is easy:
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13 :::java
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14 name = "Dirk"
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15 template = """Hello $name,
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16 I owe you \$100
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17 but I don't owe you the \$world"""
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18 println(template)
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20 Just escape the dollar sign with `\` and you're good to go.
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22 Not so in Kotlin! Using a dollar sign that's escaped with backticks will fail compilation with "unresolved reference". The documentation talks about the "valid solution" for using dollar signs:
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24 ::java
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25 fun main() {
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26 val name = "Dirk"
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27 val template = """Hello $name,
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28 I owe you $100
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29 but I don't owe you the ${'$'}world"""
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30 println(template)
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31 }
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33 Note how you don't have to escape the dollar sign in front of the number and the awkward escaping syntax.
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35 [I'm not alone with this complaint](https://youtrack.jetbrains.com/issue/KT-2425) as the discussion on the ticket shows. IMHO it's not a good sign that boasts itself for "making developers happier" when little attention to this kind of details is shown. The ticket has been open for 8 years now ...
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