W1165 Karel Introduction
Prerequisites[edit]
Background[edit]
Coder Merlin™ Karel , also known as "that little blue bot", is strongly inspired by Richard Pattis' book written during his studies at Stanford.[1][2] Richard Pattis currently teaches at the University of California, Irvine. Pattis chose the name Karel in honor of the Czech playwright Karel Čapek, who introduced the word robot in his 1921 play R.U.R.
Eric Roberts, Department of Computer Science, Stanford University, September 2005:
In the 1970s, a Stanford graduate student named Rich Pattis decided that it would be easier to teach the fundamentals of programming if students could somehow learn the basic ideas in a simple environment free from the complexities that characterize most programming languages. Drawing inspiration from the success of Seymour Papert’s LOGO project at MIT, Rich designed an introductory programming environment in which students teach a robot to solve simple problems. [3]
Coder Merlin™ Karel is a very simple robot living in a very simple world. Programming Coder Merlin™ Karel is accomplished by specifying a series of simple instructions. Coder Merlin™ Karel initially understands only a very few instructions, but over time you can expand the vocabulary by defining functions and enhancing Coder Merlin™ Karel 's abilities.
All instructions issued to Coder Merlin™ Karel must be very precise and unambiguous, a key requirement of well-written programs. The programs themselves must obey a set of syntactic rules which define which commands (and the ordering of those commands) are acceptable. These rules define a programming language, such as the Swift programming language which we've been using. The details of the subset of instructions which Coder Merlin™ Karel understands are very easy to master, enabling us to focus on problem solving.
It is problem solving which is the focus and essence of computer programming.
Introduction (Welcome to my World)[edit]
Streets, Avenues, and Corners[edit]
Coder Merlin™ Karel lives in a city with green avenues running vertically north-south and blue streets running horizontally east-west. The intersection of a street with an avenue is called a corner. Coder Merlin™ Karel can only be position on a corner and must point in one of the four cardinal directions. Coder Merlin™ Karel always points with his hat, so in Figure 1 Coder Merlin™ Karel is positioned at (avenue: 1, street: 1) and is facing north. Note that worlds may be of various sizes depending upon the challenge that needs to be solved.
Beepers[edit]
Corners may have zero or more beepers present, indicated by a yellow/red rotating beacon. The number in the center of the beacon indicates the number of beepers present on the corner. In Rich Pattis’s book, beepers are "plastic cones which emit a quiet beeping noise." Coder Merlin™ Karel can only detect a beeper if it is on the same corner. Coder Merlin™ Karel carries with him a hidden beeper bag; the number on the front of Coder Merlin™ Karel indicates how many beepers are in the bag (Figure 3).
Walls[edit]
Walls may be present between streets and avenues and serve as a barrier to Coder Merlin™ Karel ; unable to pass through them Coder Merlin™ Karel must go around them. Note that the presence of walls is implied around the boundary of the city.
Challenges[edit]
Coder Merlin™ Karel is integrated into Merlin Mission Manager but because it is built on top of IGIS[4] a few additional steps are necessary to complete Coder Merlin™ Karel challenges.
Getting Started[edit]
Syntax Highlighting[edit]
The Goal[edit]
The Instructions[edit]
Building and Running[edit]
Testing[edit]
Submission[edit]
Key Concepts[edit]
Exercises[edit]
References[edit]
- ↑ Richard E. Pattis. Karel The Robot: A Gentle Introduction to the Art of Programming. John Wiley & Sons, 1981
- ↑ https://web.stanford.edu/class/cs208e/cgi-bin/main.cgi/static/lectures/03-IntroProgramming/03-IntroProgramming.pdf
- ↑ https://web.stanford.edu/class/archive/cs/cs106a/cs106a.1194/karelReader/original.pdf
- ↑ https://github.com/TheCoderMerlin/Igis