Scala: Insert blank lines before HTML tags; convert a String to a Seq

By Alvin Alexander. Last updated: May 22, 2020

As a quick note to self, these are two Scala functions I just ran across that I’m putting here so I can find them in the future. The first function does what it says it does, inserting blank lines before HTML tags. It’s not perfect, but it’s a start for what I wanted when I couldn’t get “pretty printers” to do what I wanted:

def insertBlankLinesBeforeHtmlTags(originalHtml: String): String = {
    val htmlAsSeq = convertStringWithNewlinesToSeq(originalHtml)
    val spacedHtmlAsSeq: Seq[String] = for {
        line <- htmlAsSeq
        newLine = if (line.startsWith("<h")) {
            s"\n\n${line}"  //two blank lines before header tags
        } else if (line.startsWith("<")) {
            s"\n${line}"    //one blank line before other html tags
        } else {
            line
        }
    } yield newLine
    val htmlWithBlankLines = spacedHtmlAsSeq.mkString("\n")
    htmlWithBlankLines
}

Next, this Scala function shows how to convert a String into a Seq by splitting the string on newline characters:

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

That’s all for today. As mentioned, I just came across these functions in some old code and wanted to put them here so I could find them again if/when needed.

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Scala: Insert blank lines before HTML tags; convert a String to a Seq

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