0.16.0 — a rung may open on a date, and the clock is read at the edge
Some rungs should not open yet. A review window. A cooling-off period. A notice period somebody agreed to in a contract.
This release adds date and duration operators to the condition language, so a ladder can say so.
The clock stays outside
The interesting part is where the time comes from. The kernel deciding the move has no clock at all — reading one is banned by a scan over its own sources. The instant is read at the edge and handed in as an argument.
That is not fastidiousness. It is what makes the same inputs give the same verdict forever, so a decision recorded today can be re-checked next year by somebody who was not there, and the answer does not depend on when they asked.
A kernel that read its own clock would give different verdicts at different moments for identical inputs, and every recorded decision would become unfalsifiable.
Growing a language one operator at a time
The condition language is data, and the standing rule is that it grows operator by operator, never into a language. Two comparison operators over instants is a step; an expression evaluator would be a different product.
The part that had to be got right
Date parsing now lives inside a decision path, which means it has to be total. A malformed
date is False — not a panic, not a default, not "probably fine". Anything that can be reached by a
gate has to have an answer for every input, including the input nobody expected.