multiline string

Dart: How to remove leading spaces in a multiline string (using splitMapJoin)

As far as I know, there’s no built-in way to remove spaces from a multiline string in Dart, but you can write your own function to do this. For example, I just dug into the splitMapJoin method of the Dart String class, and wrote a stripMargin function like this:

String stripMargin(String s) {
    return s.splitMapJoin(
        RegExp(r'^', multiLine: true),
        onMatch: (_) => '\n',
        onNonMatch: (n) => n.trim(),
    );
}

How to left-justify a multiline Scala string

If you ever need to left-justify a multiline Scala string, the solution is to use the stripMargin method, as shown in this example:

def getWordFormatted(s: String): String = {
    s"""
      |
      |Word of the Day
      |---------------
      |Word: $s
    """.stripMargin
}

The | character has a special meaning when used in conjunction with stripMargin, so that method results in a string like this being output:

Scala: Convert a String with newline characters to a sequence/list of strings

If you ever need a Scala method/function to convert a string with newline characters in it to a sequence of strings (Seq[String]), here you go:

def convertStringWithNewlinesToSeq(s: String): Seq[String] =
    s.split("\n").toVector

You can convert the final result to a Vector, Seq, List, ArrayBuffer, Array, etc., but I prefer Vector. The Scala REPL demonstrates how it works:

scala> convertStringWithNewlinesToSeq("")
res0: Seq[String] = Vector("")

scala> convertStringWithNewlinesToSeq("foo")
res1: Seq[String] = Vector(foo)

scala> convertStringWithNewlinesToSeq("foo\nbar\nbaz")
res2: Seq[String] = Vector(foo, bar, baz)

scala> convertStringWithNewlinesToSeq("foo\nbar\nbaz\n\n")
res3: Seq[String] = Vector(foo, bar, baz)

How to create multiline strings in Scala

This is an excerpt from the Scala Cookbook (partially modified for the internet). This is Recipe 1.2, “How to Create Multiline Strings in Scala.”

Problem

You want to create multiline strings within your Scala source code, like you can with the “heredoc” syntax of other languages.

Solution

In Scala you create multiline strings by surrounding your text with three double quotes: