SLIDE 1
BugsWorld Introduction
27 February 2019 OSU CSE 1
BugsWorld
- You will be working on projects related to
various aspects of a game called BugsWorld:
– The Game – The Simulator – The Language – The Compiler
27 February 2019 OSU CSE 2
BugsWorld Introduction 27 February 2019 OSU CSE 1 BugsWorld You - - PowerPoint PPT Presentation
BugsWorld Introduction 27 February 2019 OSU CSE 1 BugsWorld You - - PowerPoint PPT Presentation
BugsWorld Introduction 27 February 2019 OSU CSE 1 BugsWorld You will be working on projects related to various aspects of a game called BugsWorld : The Game The Simulator The Language The Compiler 27 February 2019 OSU
SLIDE 2
SLIDE 3
The Game: It’s a Bug’s World!
27 February 2019 OSU CSE 3
SLIDE 4
The Simulator
- The BugsWorld game is played on a
system consisting of:
– Server – Clients – Displays
27 February 2019 OSU CSE 4
SLIDE 5
The Simulator
- The BugsWorld game is played on a
system consisting of:
– Server
27 February 2019 OSU CSE 5
The server keeps track
- f “the world”,
processes client requests, resolves conflicts.
SLIDE 6
The Simulator
- The BugsWorld game is played on a
system consisting of:
– Server – Clients
27 February 2019 OSU CSE 6
Each client program simulates creature (bug) behavior for all creatures of one species.
SLIDE 7
The Simulator
- The BugsWorld game is played on a
system consisting of:
– Server – Clients – Displays
27 February 2019 OSU CSE 7
Each display shows the current state of the world, plus some statistics about the simulation.
SLIDE 8
The Simulator
- The BugsWorld game is played on a
system consisting of:
– Server – Clients – Displays
27 February 2019 OSU CSE 8
Each process can run
- n a different computer
(distributed simulation).
SLIDE 9
The Language
- The behavior of each species is determined by a
program in the language BL
- Primitive instructions: move, turnleft, turnright,
infect, skip
- Control structures: IF-THEN, IF-THEN-ELSE,
WHILE-DO
- Defining new instructions: INSTRUCTION-IS
- Conditions: test whether “next” cell is empty,
friend, enemy, or wall (plus true and random)
27 February 2019 OSU CSE 9
SLIDE 10
BL Program Example
PROGRAM TryToGuess IS INSTRUCTION FindObstacle IS WHILE next-is-empty DO move END WHILE END FindObstacle ...
27 February 2019 OSU CSE 10
SLIDE 11
BL Program Example
PROGRAM TryToGuess IS INSTRUCTION FindObstacle IS WHILE next-is-empty DO move END WHILE END FindObstacle ...
27 February 2019 OSU CSE 11
See next slide...
SLIDE 12
BL Program Example (Cont’d)
BEGIN WHILE true DO FindObstacle IF next-is-enemy THEN infect ELSE IF next-is-wall THEN turnleft ELSE skip END IF END IF END WHILE END TryToGuess
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SLIDE 13
BL Features
- Precise syntax
- Case sensitive
- Matching ENDs
- Identifiers:
– Start with any of 'a'..'z', 'A'..'Z' – Followed by any of 'a'..'z', 'A'..'Z', '0'..'9', '-'
27 February 2019 OSU CSE 13
SLIDE 14
The Compiler
PROGRAM TryToGuess IS INSTRUCTION FindObstacle IS WHILE next-is-empty DO move END WHILE END FindObstacle BEGIN WHILE true DO FindObstacle IF next-is-enemy THEN infect ELSE IF next-is-wall THEN turnleft ELSE skip END IF END IF END WHILE END TryToGuess
27 February 2019 OSU CSE 14
<20, 15, 20, 6, 7, 0, 5, 2, 12, 12, 3, 5, 18, 8, 17, 1, 5, 18, 4, 5, 0>
SLIDE 15
The Compiler
PROGRAM TryToGuess IS INSTRUCTION FindObstacle IS WHILE next-is-empty DO move END WHILE END FindObstacle BEGIN WHILE true DO FindObstacle IF next-is-enemy THEN infect ELSE IF next-is-wall THEN turnleft ELSE skip END IF END IF END WHILE END TryToGuess
27 February 2019 OSU CSE 15
<20, 15, 20, 6, 7, 0, 5, 2, 12, 12, 3, 5, 18, 8, 17, 1, 5, 18, 4, 5, 0> This string of integers is the object code for the BL program source code shown
- n the left.
SLIDE 16
Compiler Structure
27 February 2019 OSU CSE 16
Code Generator Parser Tokenizer string of characters (source code) string of tokens (“words”) abstract program string of integers (object code)
SLIDE 17
What You Will Do
- You will implement at least major parts of
all three pieces of the BL compiler:
– Tokenizer – Parser – Code Generator
27 February 2019 OSU CSE 17