Weekly Note 4, DM18, Spring 2007

Lecture February 13

• Abstract syntax trees.
• Weeding, symbol tables, and type check.

Exercises February 15

• Extend tiny expressions with a modulo operator % and an absolute value funktion |_|.
• Introduce unary minus, -x, into the language as so-called syntactic sugar for 0-x, i.e., you may write -x according to the new grammar, but internally (in the AST), it is just represented as 0-x.
• Discuss in detail how you can avoid building lists backwards in an LALR(1) parser. Rewrite the lecture example to obtain this.
• Appel 5.1 a; do this with basis in you own implementation of a hash table.

Announcements

• Please check the list of participants and groups and report any error to the lecturer by e-mail.
• On the list of participants as well as on the project parts you turn in, it is important to list your full name. We have seen repeatedly that people who use a middle name as either their first name or their last name, do not comply with this. Often, this can result in administrative difficulties for these people as they may not get registered at the administrative level as having turned in their project.