A Project Approach to Programming Language Theory Joan Krone Denison University

2 Many Languages Natural6,912 Millennia to develop Programming 2,500 (U. of Kansas) 8,500 (Diarmuid Piggott) all within 50 years One language per week since Fortran based on the 2,500

3 Where Have All the Languages Gone? Assembler Fortran Basic Pascal PL1 Modula2 Ada C C++ Lisp/Scheme ML Clu Prolog Smalltalk Eiffel Python Perl Java PHP HTML

4 Recent Article Ryder, Soffa, Burnett, “The Impact of Software Engineering Research on Modern Programming Languages,” ACM TOSEM, 2005.

5 Paradigms Logic Structured Procedural OO Use of Abstraction (java interfaces)

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7 Why Johnny Can’t Code David Brin Language for novices?

8 The Problem Maybe Basic Probably java Lack of student experience

9 Two Levels of Programming Language Courses Sophomore Level: survey Senior Level: capstone

10 A Two Pronged Approach Semester Project Daily assignments –Same questions –Different languages for different students

11 Project Choices 1.Become a guru. 2.Do a comparative analysis of 2 languages in the same category. C++ and Java Perl and HTML 3.Do a comparative analysis of 2 languages in the different categories. Java and Scheme Haskell and Python

12 4.Write a translator for a simple language. 5.Design a new language.

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14 To Be a Guru Classify History Scoping Type Checking Support for Abstraction Concurrency Type Conversion

15 Write documentation Choose at least 3 features unique to your language and explain how those features can be used advantageously by a programmer to perform some task in your language more efficiently than it could be done in another language without those features. Be prepared to give a talk and a demonstration which illustrate how your language facilitates the implementation of solutions to problems.

16 Daily Requirement Choose a language Discover how that language handles a particular topic, such as scoping. Prepare a demo to illustrate the discovery

17 Class Size Small class - - individual investigations Large class - - groups of 2, 3, or 4

18 Programming Languages are Like Cars Assembler: A formula I race car. Very fast but difficult to drive and maintain. FORTRAN II: A Model T Ford. Once it was the king of the road. FORTRAN IV: A Model A Ford. FORTRAN 77: a six-cylinder Ford Fairlane with standard transmission and no seat belts. COBOL: A delivery van. It's bulky and ugly but it does the work. BASIC: A second-hand Rambler with a rebuilt engine and patched upholstery. Your dad bought it for you to learn to drive. You'll ditch it as soon as you can afford a new one. PL/I: A Cadillac convertible with automatic transmission, a two-tone paint job, white-wall tires, chrome exhaust pipes, and fuzzy dice hanging in the windshield.

19 Pascal: A Volkswagon Beetle. It's small but sturdy. Was once popular with intellectual types. LISP: An electric car. It's simple but slow. Seat belts are not available. PROLOG/LUCID: Prototype concept cars. FORTH: A go-cart. LOGO: A kiddie's replica of a Rolls Royce. Comes with a real engine and a working horn. APL: A double-decker bus. It takes rows and columns of passengers to the same place all at the same time but it drives only in reverse and is instrumented in Greek. Ada: An army-green Mercedes-Benz staff car. Power steering, power brakes, and automatic transmission are standard. No other colors or options are available. If it's good enough for generals, it's good enough for you. C++: A black Firebird, the all macho car. Comes with optional seatbelt (lint) and optional fuzz buster (escape to assembler). Java: All-terrain very slow vehicle.

20 Our Future C++ and Java forever? Probably Not Our students may be the designers of the next important language Hopefully, they will learn from history