changeset 104:c56fdf7a343d

New blog post about Kotlin's multiline strings
author Dirk Olmes <dirk.olmes@codedo.de>
date Fri, 12 Jun 2020 12:56:06 +0200
parents 6aa2fa328a94
children 932436ea5196
files content/Kotlin/multiline-strings.md
diffstat 1 files changed, 36 insertions(+), 0 deletions(-) [+]
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+Title: Kotlin multiline strings vs the $ character
+Date: 2020-06-12
+Lang: en
+
+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.
+
+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 `$` character.
+
+Kotlin, much like [Groovy](https://groovy-lang.org/) supports multiline strings. It also allows the use of `$`-epxressions in the string. Things start to become difficult if you need a literal dollar sign in the string.
+
+Embedding literal dollar signs in Groovy multiline strings is easy:
+
+	:::java
+	name = "Dirk"
+	template = """Hello $name, 
+		I owe you \$100 
+		but I don't owe you the \$world"""
+	println(template)
+
+Just escape the dollar sign with `\` and you're good to go.
+
+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:
+
+	::java
+	fun main() {
+		val name = "Dirk"
+		val template = """Hello $name, 
+			I owe you $100 
+			but I don't owe you the ${'$'}world"""
+	    println(template)
+	}
+
+Note how you don't have to escape the dollar sign in front of the number and the awkward escaping syntax.
+
+[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 ...
+