This volume contains 15 papers from research areas where Japanese theoretical computer science is particularly strong. The purpose of this volume is to celebrate Professor Takasu's influence on theoretical computer science in Japan and worldwide by his research, his philosophy, and his advising of students.

Lifschitz's logic of calculable numbers and optimizations in program extraction.- On implicit arguments.- A functional system with transfinitely defined types.- The non-deterministic catch and throw mechanism and its subject reduction property.- Conservativeness of ? over ??-calculus.- ML with first-class environments and its type inference algorithm.- A simple proof of the genericity lemma.- The logic of FOL systems: Formulated in set theory.- Well-ordering of algebras and Kruskal's theorem.- On locomorphism in analytical equivalence theory.- Analysis of a software/hardware system by tense arithmetic.- The essence of program transformation by partial evaluation and driving.- Program transformation via contextual assertions.- On coding theorems with modified length functions.- Thirty four comparisons are required to sort 13 items.