/*
 * Copyright (C) 2007-2020 Artima, Inc. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * Automatically generated Scala interpreter transcript from:
 *
 * Programming in Scala (Fifth Edition)
 * by Martin Odersky, Lex Spoon, Bill Venners, and Frank Sommers
 *
 * http://booksites.artima.com/programming_in_scala_5ed
 */


scala>   trait Philosophical:
           def philosophize = "I consume memory, therefore I am!"

                            ^
       error: ';' expected but ':' found.

scala>   class Frog extends Philosophical:
           override def toString = "green"

                                         ^
       error: ';' expected but ':' found.

scala>    class Rational(n: Int, d: Int) extends Ordered[Rational]:
           def compare(that: Rational) =
             (this.numer * that.denom) - (that.numer * this.denom)

        private val g = gcd(n.abs, d.abs)
        val numer = n / g
        val denom = d / g
        private def gcd(a: Int, b: Int): Int =
          if (b == 0) a else gcd(b, a % b)
        override def toString = s"$numer/$denom"
                                                                  ^
       error: ';' expected but ':' found.

scala>   abstract class IntQueue:
           def get(): Int
           def put(x: Int): Unit

                                ^
       error: ';' expected but ':' found.

scala>   import scala.collection.mutable.ArrayBuffer
       
         class BasicIntQueue extends IntQueue:
           private val buf = ArrayBuffer.empty[Int]
           def get() = buf.remove(0)
           def put(x: Int) = buf += x

                class BasicIntQueue extends IntQueue:
                                                    ^
On line 3: error: ';' expected but ':' found.

scala>   trait Doubling extends IntQueue:
           abstract override def put(x: Int) = super.put(2 * x)

                                        ^
       error: ';' expected but ':' found.

scala>   trait Incrementing extends IntQueue:
           abstract override def put(x: Int) = super.put(x + 1)
       

                                            ^
       error: ';' expected but ':' found.

scala>   trait Filtering extends IntQueue:
           abstract override def put(x: Int) =
             if x >= 0 then super.put(x)

                                         ^
       error: ';' expected but ':' found.
                    if x >= 0 then super.put(x)
                              ^
On line 3: warning: then is a reserved word (since 2.10.0); usage as an identifier is deprecated

scala> val frog = new Frog("Hopscotch")
                      ^
       error: not found: type Frog