Sunday, February 26, 2012

Episode 11: Lisp

Hey all,

Life got in the way of the podcast for awhile so myself and Patrick had to take a brief hiatus.  This episode was recorded before things got crazy, but I wanted to let everyone know that the podcast is coming back and we will begin recording new episodes in the next couple of weeks.

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News
Tool of the Biweek

Lisp

History
  • Invented before it was implemented
  • Foundational registers
    • car (Contents of the Address part of Register number)
    • cdr (Contents of the Decrement part of Register number).
  • Based on lambda calculus
  • Lisp Machines

Uses
  • Artificial Intelligence
    • Planning
    • Expert Systems
    • SHRDLU (Natural Language Processing)
  • Emacs
  • ITA - Backend airline software
  • Maxima: Computer Algebra System

Features
  • S-Expressions (car cdr)
  • “Easy” to implement an interpreter/compiler
    • Many dialects



Strengths

  • Extremely efficient hashtables
  • Easy to parse code & automatically generate code
    • Self-modifiable code


Weaknesses


  • All those parentheses
  • No direct memory access, poor hardware access