Elamur Groupantslatex-build-stage2
The groupant beside latex/build.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 |
| composition | partial | composition |
| descriptant | present | descriptant |
| invariant | partial | invariant |
| tests | executed 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 |
discriminant_transport | discriminant_transport | partial source derived model | discriminant_transport |
optional_canonical | optional_canonical | partial source derived model | optional_canonical |
Model text
descriptant
latex-build-stage2
Given validated ordered rows, emission writes Sym variants and SYM_LATEX/TEXT/CLASS/DELIM/ALL in the same index order. Fixed docs array orders the seven other enums. Lookup matches enumerate accumulated command, character and environment vectors and end in None. Finally require OUT_DIR and fs::write its table.rs.
Epoch 2026-10-31: replaced stage topic lists with concrete transitions, exclusions and compatible antecedents. Four meaningful typed views replace the previous six-view bookkeeping catalog. Shared syntax and source byte bounds are unchanged.
approximant
Scoped forward relation
Given validated ordered rows, emission writes Sym variants and SYM_LATEX/TEXT/CLASS/DELIM/ALL in the same index order. Fixed docs array orders the seven other enums. Lookup matches enumerate accumulated command, character and environment vectors and end in None. Finally require OUT_DIR and fs::write its table.rs.
This is an exact source-derived partial model, not an executable approximate replacement.
invariant
Scoped invariants
Array metadata cannot be independently reordered by HashMap iteration in this implementation. No runtime disk-reading lookup is generated. Successful emission cannot assign two explicit match arms from one rejected duplicate input; write errors panic rather than return a successful build.
For row i, Sym variant discriminant i indexes all four metadata arrays and SYM_ALL[i]. A manual reorder of only one array would break the parser/printer join.
FracKind has independent Option prefix/infix forms; EnvKind has independent Option begin-name/plain forms. Other enum families require a canonical form and panic if absent during emission.
composition
Scoped interaction
table.rs includes this generated output. Emission assumes validation's references and row order; it is not independently validating arbitrary generated Rust.
The manifest binds this stage to the unchanged parent syntax projection and exact source byte range. Parent cost remains an upper accounting context; no independent whole-file invocation or execution count is assigned to this fragment.
models
behavior_complement
Array metadata cannot be independently reordered by HashMap iteration in this implementation. No runtime disk-reading lookup is generated. Successful emission cannot assign two explicit match arms from one rejected duplicate input; write errors panic rather than return a successful build.
reverse_reconstruction
Generated text determines ordered enum variants and emitted mappings, but many input tables with different comments and equivalent canonical/alias construction produce it. OUT_DIR location is absent from generated text; output bytes do not reconstruct the build environment or prior file contents.
discriminant_transport
For row i, Sym variant discriminant i indexes all four metadata arrays and SYM_ALL[i]. A manual reorder of only one array would break the parser/printer join.
optional_canonical
FracKind has independent Option prefix/infix forms; EnvKind has independent Option begin-name/plain forms. Other enum families require a canonical form and panic if absent during emission.
tests
Evidence — 2026-10-31
wave28_tests::canonical_first_form_and_variant_order; wave28_tests::variant_identifier_boundary
Selected library filters ast:: lex:: macros:: parse:: print:: table:: and integration gate excluding document_extraction_with_preamble_macros and random_token_soup_never_panics_and_roundtrips. Direct rustc --test latex/build.rs exercises private helpers. All selected tests twice debug/release with identical sorted names. Four compiled mutants at build/AST/parser/printer boundaries fail assertions then exact restoration passes. These do not individually cover every source. Build-main failure effects, allocation failures and universal roundtrip are unproved. Strict Clippy reports existing lints. No corpus/live VMM/API/GPU/full-school/held-out tests.
This page in Markdown → https://md.groupants.elamur.ai/free/en/mova/latex/build.rs.groupant/stage2.groupant/