tasks a-s

Task/Regular-expressions/Scala/regular-expressions-1.scala

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+val Bottles1 = "(\\d+) bottles of beer".r                                            // syntactic sugar
+val Bottles2 = """(\d+) bottles of beer""".r                                         // using triple-quotes to preserve backslashes
+val Bottles3 = new scala.util.matching.Regex("(\\d+) bottles of beer")               // standard
+val Bottles4 = new scala.util.matching.Regex("""(\d+) bottles of beer""", "bottles") // with named groups

Task/Regular-expressions/Scala/regular-expressions-2.scala

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+"99 bottles of beer" matches "(\\d+) bottles of beer" // the full string must match
+"99 bottles of beer" replace ("99", "98") // Single replacement
+"99 bottles of beer" replaceAll ("b", "B") // Multiple replacement

Task/Regular-expressions/Scala/regular-expressions-3.scala

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+"\\d+".r findFirstIn "99 bottles of beer" // returns first partial match, or None
+"\\w+".r findAllIn "99 bottles of beer" // returns all partial matches as an iterator
+"\\s+".r findPrefixOf "99 bottles of beer" // returns a matching prefix, or None
+Bottles4 findFirstMatchIn "99 bottles of beer" // returns a "Match" object, or None
+Bottles4 findPrefixMatchOf "99 bottles of beer" // same thing, for prefixes
+val bottles = (Bottles4 findFirstMatchIn "99 bottles of beer").get.group("bottles") // Getting a group by name
+val Bottles4(bottles) = "99 bottles of beer" // syntactic sugar (not using group name)

Task/Regular-expressions/Scala/regular-expressions-4.scala

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+val Some(bottles) = Bottles4 findPrefixOf "99 bottles of beer" // throws an exception if the matching fails; full string must match
+for {
+  line <- """|99 bottles of beer on the wall
+             |99 bottles of beer
+             |Take one down, pass it around
+             |98 bottles of beer on the wall""".stripMargin.lines
+} line match {
+  case Bottles1(bottles) => println("There are still "+bottles+" bottles.") // full string must match, so this will match only once
+  case _ =>
+}
+for {
+  matched <- "(\\w+)".r findAllIn "99 bottles of beer" matchData // matchData converts to an Iterator of Match
+} println("Matched from "+matched.start+" to "+matched.end)

Task/Regular-expressions/Scala/regular-expressions-5.scala

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+Bottles2 replaceFirstIn ("99 bottles of beer", "98 bottles of beer")
+Bottles3 replaceAllIn ("99 bottles of beer", "98 bottles of beer")