Log of changes on okmij.org

April 7, 2026

Further updated and extended notes for the course Compilers: Incrementally and Extensibly. Included in the public notes now is the section on languages, grammars, parsing.

MetaOCaml: Ten Years Later. The full, 2.5x extended paper published in Science of Computer Programming
Nested grouping-aggregation: Vertical monoid composition A slightly simpler, and faster, algorithm and a better explanation
Generating parallel map-reduce for nested grouping-aggregation. Generating first-order, imperative and indeed performant code
Handling Scope Checks: A Comparative Framework for Dynamic Scope Extrusion Checks. Published in PACMPL (POPL), 2026.
Generating Code along with Annotations, on an apt example suggested by Olivier Danvy long time ago. An OlivierFest paper.

Anaphora in Static Orthodox First-Order Logic: intra- and inter-sentential, bound-variable and donkey anaphora in the the 1920s logic

Teaching Compilers: Incrementally and Extensibly once more. The course notes are updated and extended. The significantly re-written Section 3 of the course notes (starts on p.12) now gives a very simple introduction to optimization in the tagless-final style without re-writing or pattern-matching, using normalization-by-evaluation instead.

More Fun with Monoids and Map-Reduce: with quite more explanations -- in particular, of the parallel Horner rule (relating to outer semidirect product) and Boyer-Moore majority voting. Added the complete OCaml code for the parallel nested-aggregation, using OCaml domains.

Nested grouping-aggregation: Vertical monoid composition. Nested grouping-aggregation (Advent of Code 2022 Problem 1) embarrassingly in parallel, with linear speed-up.