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Unit 4: LISP
The reliance on expressions gives the language great flexibility. Because LISP functions are Notes
themselves written as lists, they can be processed exactly like data. This allows easy writing of
programs which manipulate other programs (meta programming).
Many LISP dialects exploit this feature using macro systems, which enables extension of the
language almost without limit. A LISP list is written with its elements separated by whitespace,
and surrounded by parentheses. The empty list () is also represented as the special atom nil. This
is the only entity in LISP which is both an atom and a list.
The following industrial LISP users are grouped by industry:
Aerospace/Airlines
Animation/Graphics
Automotive
Computers and Computer Tools
Computer-aided Design
Consulting/Research
Databases
Expert Systems and Knowledge-based Engineering Tools
Education
Electronics
Energy
Finance
Government
Groupware/Project Management
Internet/World-Wide-Web
Publishing
Mathematics
Medicine/Biotechnology
Music
Telecommunications
Other
Self Assessment
State whether the following statements are true or false:
1. LISP is an expression-oriented language.
2. McCarthy’s 1958 paper introduced four types of syntax.
3. A LISP list is written with its elements separated by whitespace, and surrounded by
parentheses.
4. The empty list () is not represented as the special atom nil.
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