DSLs:
A Logical Approach

Fall 2001.

Subject

Making languages bear-able:

For I am a bear of very little brain and long words confuse me.

Milne 1926

The premise of this subject is that computers should adapt to the ways of people, and not the other way around.

One method for doing this is a domain-specific langauge (DSL). A DSL is a very high-level language that a user can learn and use in less than a day. Such productivity can only be achieved by tailoring the language to the special needs and skills of a particular class of users in a particular domain.

In a DSL-based software development process, the analyst:

Identifies the users and their tasks;
Identifies the common idioms used by those users;
Invents a declarative language to handle those idioms;
Generates sample sentences in that language;
Shows those sentences to the user and trains them how to write their own.

That is, instead of the analyst writing the application, the analysts writes tools that let a user community write and maintain their own knowledge.

The benefits of DSL (productivity, explanatory, ownership by the users) can be out-weighed by the cost of building the DSL. Traditional methods for DSL construction include writing interpreters of some domain-specific syntax into some procedural language (e.g. AWK, Perl, Java, etc). This subject offers a more general approach in which:

The DSL syntax is expressed as logical horn clauses using Prolog's infix operator notation.
Interpreters and meta-interpreters are used to execute that syntax.
The DSL system is explored using stochastic abduction (for what-if queries) and treatment learners (to find controllers for that system).

In this subject, students will:

Study all the terms shown above in italics
Examine case studies of successful DSLs.
Build their own DSL, optimize it with a compiler, study it using abduction, then learn controllers for their DSL system.

Subject timetable

Where:: MCLD 402
When:: Mondays, 2pm - 5pm

NOTE: No lecture in week 1 of the fall 2001 term.

Lecturer

Who:: Dr. Tim Menzies (PhD, AI, UNSW, 1995)
Room:: MCLD 341
Phone:: 604-822-3381
Email:: tim@menzies.com
Career:: Australian lost in North America for a while. Ex-nurse, ex-taxi driver, , ex-OO consultant, ex-NASAish. Mad. Keen. Mad keen on applying artificial intelligence techniques to software engineering. Been using logic programming to write DSLs for years. Wrote Australia's first exported expert system in 1988- which was a DSL (of course) [Menzies, et.al. 1988].

Textbook

No textbook for logic-based DSLs exist. Instead, students should get the excellent Prolog Programming for Artificial Intelligence by Ivan Bratko (third edition, Addison Wesley).

Assessment

No exams.

15% Participation in discussions.

15% Assignment 1

20% Assignment 2

25% Assignment 3

25% Assignment 4

Special Consideration

Students requesting special consideration regarding poor marks must provide documentary evidence for the reason of the poor marks (e.g. doctor's certificates).

Assignments

Four assignments due Friday week 4,7,10,and 13:

Parse a DSL
Build a DSL interpreter
Build a DSL compiler
Use treatment learning to find controllers for a DSL.

For more details, see the assignments page.

Mailing list

All students should join this subject's news group. Note: to do so, I think you also have to join up to Yahoo.

Once joined it is very important that students go to the "Subscribe" page and select "Send email messages to <your email>" option in the section Message Delivery:

Not © Tim Menzies, 2001
Share and enjoy- information wants to be free.
But if you take anything from this site,
please credit tim@menzies.com.

DSLs:A Logical Approach