gistfile1.scala

case class PrintfCall(format: String, arguments: Seq[Expression]) extends Expression {
  def sanitized(implicit sink: DiagnosticSink): PrintfCall = {
    if ("""%[^diouxxcs%]""".r.findAllIn(format + "\0").isEmpty) {
      val count = """%[diouxxcs]""".r.findAllIn(format).size
      if (arguments.size < count) sink.error("not enough arguments to printf")
      if (arguments.size > count) sink.warning("too many arguments to printf")
    } else {
      sink.error(s"illegal or unfinished conversion specifier inside format string")
    }
    this
  }
}