Download History of Lisp

History of Lisp
And Functional Programming
Languages
Scotty Smith
Overview
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Lambda Calculus
History of Lisp
Key Features of Functional Languages
Haskell
Why no one uses functional languages
Lambda Calculus
• Developed by Alonzo Church in the 1930’s
• Type Free
• Deals with recursion, higher-order
functions, and currying
λx.x+1 ≡ fun x => x+1
The Beginnings of LISP
• John McCarthy -1956
• Dartmouth summer research project on
Artificial Intelligence.
• IBM 704
FLPL: FORTRAN List Processing
Language
• Implemented at IBM by Herbert Gelernter
and Carl Gerberich
• Written as an extension of FORTRAN
Conditional Expressions
• Developed in 1957 – 1958 at MIT.
• XIF(M,N1,N2).
• Developed a true conditional that evaluated
only one of its parameters.
Innovations Beyond FLPL
• Recursive functions using conditional
expressions
• Maplist
Implementation of LISP
• Fall of 1958
• MIT
• Started by hand compiling functions written in
M-expressions
• Prefix notation
• Contains side effects
Turing Machines and LISP
• The universal LISP function
• eval[e,a]
• e – The LISP expression
• a – a list of assignments of values to variables
The Interpreter
• Written by S.R. Russell
• Froze the development of the form of the
language.
Moving On
• Lisp 1.5
• Insertion of elements into lists and deletion
• Lexical scoping
• FUNARG device
• A compiler
Other contributions of LISP
• Garbage collection
LISP example
• (defun factorial (n)
(if (<= n 1)
1
(* n (factorial (- n 1)))))
Key Features of Functional
Languages
• Higher Order functions
• Curried functions
• Lazy Evaluation (Non-strict Evaluation)
• Static typing
• Pattern Matching
• Guards
• fac 0 = 1
fac n|n>0 = n*fac(n-1)
Haskell
• Purely functional language
• Attempt at a standard functional language
• Features
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Higher order functions
Lazy evaluation
Static polymorphic typing
User-defined datatypes
Pattern matching
List comprehensions
• New to Haskell
• I/O system
• Overloading
• Array comprehensions
Why no one uses functional
languages
• Portability/Availability
• Training
• Popularity
References
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Hudak, P. 1989. Conception, evolution, and application of functional programming
languages. ACM Comput. Surv. 21, 3 (Sep. 1989), 359-411. DOI=
http://doi.acm.org/10.1145/72551.72554
McCarthy, J. 1978. History of Lisp. In Preprints of Proceedings of ACM SIGPLAN
History of Programming Languages Conference. SIGPLAN Notices, Vol. 13, pp. 217223
Wadler, Phillip. “Functional Programming: Why no one uses functional languages”
SIGPLAN Notices 33(8):23-27, August 1998.