Download 1-Introduction and overview

Computer Science 312
Programming Language Design
Course Goals
•  Experience different programming language styles
•  Learn to write interpreters for different languages
•  Learn to program in Scheme, Erlang, and
Smalltalk
•  Have some FUN!
Computer Science
•  Algorithms and data
structures
•  Computer organization
•  Theory of computation
•  Programming
language design
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Database management
Artificial intelligence
Operating systems
Compiler construction
Graphics and image
processing
•  Networks
Computer as a Layered System
Transistors
Logic Circuits
Multiplexors
Etc.
Hardware
Memory
ALU
Control Unit
I/O Devices
A program and its data are patterns of voltage levels
Computer as a Layered System
Machine language
Hardware
001110100101
010010000011
110001010111
111111100000
001010100001
A program and its data are patterns of 1s and 0s
Computer as a Layered System
Assembly language
Hardware
in length
in width
load length
mul width
store area
out area
halt
A program and its data are patterns of mnemonic symbols
Computer as a Layered System
High-level language
Hardware
while x > 0:
if x % 2 == 0:
evens = evens + 1
else:
odds = odds + 1
x=x-1
A program and its data are patterns of arbitrary symbols,
with lots of structure for the programmer
Software Tools
File manager
Editor
Assembler
Linker
Loader
Run-time system
Hardware
Debugger
Profiler
CASE tools
History of Programming
Languages
•  To a certain extent, the layers of
programming languages mirror their
historical evolution
5 Generations of Languages
Hardware
History and Evolution
First
1950
1960
1970
1980
Second
Third
Fourth
Fifth
Machine
Assembly
FORTRAN
ALGOL
COBOL
LISP
PASCAL, C
PROLOG
Modula Smalltalk
Ada
Erlang
C++, Java, and Python are hybrids of fourth and fifth
First Generation Languages
•  Machine language
•  Assembly language
•  FORTRAN (FOrmula TRANslation Language)
First Generation Languages
•  Programs have a linear structure, isomorphic
with the underlying machine structure
•  But FORTRAN allows algebraic notation
Second Generation Languages
•  ALGOL (ALGOrithmic Language)
•  COBOL (COmmon Business-Oriented Language)
•  PL/1
Second Generation Languages
•  Programs are hierarchical in structure
•  Recursion
•  Wide variety of data types and strong type
checking
Third Generation Languages
•  Pascal
•  C
Third Generation Languages
•  Hierarchical data structures (arrays, records)
•  Dynamic memory (pointers)
Fourth Generation Languages
•  Modula
•  Ada
Fourth Generation Languages
•  Support for information hiding in packages or
modules
Fifth Generation Languages
•  LISP (LISt Processing Language)
•  Smalltalk
•  PROLOG (PROgramming in LOGic)
•  Erlang
Fifth Generation Languages
Support for new paradigms of programming:
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Function-oriented (LISP)
Object-oriented (Smalltalk)
Logic-oriented (PROLOG)
Concurrency-oriented (Erlang)
Multiple Models of Computation
Objects Processes
Hardware
von Neumann
Functions
Logic