Scala example source code file (StripMarginInterpolator.scala)

This example Scala source code file (StripMarginInterpolator.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Scala source code examples by using tags.

All credit for the original source code belongs to scala-lang.org; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Scala tags/keywords

any, char, list, nil, string, stringcontext, stringlike, stripmargininterpolator

The StripMarginInterpolator.scala Scala example source code

package scala
package reflect
package internal
package util

trait StripMarginInterpolator {
  def stringContext: StringContext

  /**
   * A safe combination of [[scala.collection.immutable.StringLike#stripMargin]]
   * and [[scala.StringContext#raw]].
   *
   * The margin of each line is defined by whitespace leading up to a '|' character.
   * This margin is stripped '''before''' the arguments are interpolated into to string.
   *
   * String escape sequences are '''not''' processed; this interpolater is designed to
   * be used with triple quoted Strings.
   *
   * {{{
   * scala> val foo = "f|o|o"
   * foo: String = f|o|o
   * scala> sm"""|${foo}
   *             |"""
   * res0: String =
   * "f|o|o
   * "
   * }}}
   */
  final def sm(args: Any*): String = {
    def isLineBreak(c: Char) = c == '\n' || c == '\f' // compatible with StringLike#isLineBreak
    def stripTrailingPart(s: String) = {
      val (pre, post) = s.span(c => !isLineBreak(c))
      pre + post.stripMargin
    }
    val stripped: List[String] = stringContext.parts.toList match {
      case head :: tail => head.stripMargin :: (tail map stripTrailingPart)
      case Nil => Nil
    }
    new StringContext(stripped: _*).raw(args: _*)
  }
}