roundtrip-tree-orders

The groupant beside tools/roundtrip/src/tree.rs in the Mova repository: what the code computes, what it never does, how to go back from its outputs, its invariants, cost and checks.

Facts

Implementation material. A Mova code model describes this code at one source revision: partial models, finite checks and their stated scope. It is not a reviewed general exposition, and its labels are shown as written, never raised.

Components

component	label	where
approximant	partial	approximant
ast	partial	`../syntax.json`
cost	partial	invariant-and-cost
descriptant	present	descriptant
invariant	partial	invariant-and-cost
tests	bounded checks	tests

Obernants

The typed relations around the forward model: the behaviour complement (what the code never does), the reverse reconstruction (every input compatible with an output) and specialised views.

id	type	label	where
`behavior_complement`	behavior_complement	partial source derived model	behavior_complement
`reverse_reconstruction`	reverse_reconstruction	partial source derived model	reverse_reconstruction
`coordinate_domains`	coordinate_domains	partial source derived model	coordinate_domains
`projectivity_domain`	projectivity_domain	partial source derived model	projectivity_domain
`scope_precondition`	scope_precondition	partial source derived model	scope_precondition
`resource_boundary`	resource_boundary	partial source derived model	resource_boundary

Model text

descriptant

Tree ordering coordinates

2026-10-31 epoch: source scope bytes [3856,6005); Rooted acyclic kids lists yield local child/head orders; projective permutations are reconstructed by emit, crossing arrangements need Full residual.

No annotator/model loading, live corpus, full suite, teacher, GPU or persistent-learning evidence. No executable percentage surrogate: categorical codecs/effects need a useful metric before future caps 1/2/5/10%.

approximant

Tree ordering coordinates

Rooted acyclic kids lists yield local child/head orders; projective permutations are reconstructed by emit, crossing arrangements need Full residual.

Domain: bounded synthetic values, valid source-specific coordinates, nonoverflowing counts, available allocation; fixed environment controls. Relations are source-derived partial models with finite checks, not universal proofs.

catalog

behavior_complement

Subject: roundtrip-tree-orders, source hash 3db953874807575403c8d2857006e1932cc72df16fa615b64c5b9e7eceae8da7, transition observation.

For Tree ordering coordinates, excluded transitions violate the stated scoped rule: Rooted acyclic kids lists yield local child/head orders; projective permutations are reconstructed by emit, crossing arrangements need Full residual. This is an inner source-derived exclusion under the domain, not a complement of arbitrary unseen runtime behavior.

Evidence: external wave32 rt_core receipt includes native-commands.json, exact named outcomes twice debug/twice release, raw status/log files, compiled production controls with byte restoration and paired syntax. Only named synthetic helpers execute; model_path/export and live CLI paths have representation/source evidence.