Elamur Groupantslatex-build
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 |
canonical_selection | canonical_selection | partial source derived model | canonical_selection |
duplicate_precedence | duplicate_precedence | partial source derived model | duplicate_precedence |
generated_transport | generated_transport | partial source derived model | generated_transport |
effect_boundary | effect_boundary | partial source derived model | effect_boundary |
Parts
Model text
descriptant
latex-build
En::canon/alt retain first form; variants retain first-seen order. main validates row arity, identifier, symbol uniqueness and class before forms; explicit characters claim slots before automatic text fallback. Fixed enum emission order avoids HashMap iteration nondeterminism; writes OUT_DIR/table.rs only after validation.
Epoch2026-10-31: full source reviewed before edits; prospective models retained externally. No optimization.
approximant
Forward relation
En::canon/alt retain first form; variants retain first-seen order. main validates row arity, identifier, symbol uniqueness and class before forms; explicit characters claim slots before automatic text fallback. Fixed enum emission order avoids HashMap iteration nondeterminism; writes OUT_DIR/table.rs only after validation.
No useful approximate executable metric for exact categorical syntax; future caps1/2/5/10% only.
invariant
Domain, invariant and cost
En::canon/alt retain first form; variants retain first-seen order. main validates row arity, identifier, symbol uniqueness and class before forms; explicit characters claim slots before automatic text fallback. Fixed enum emission order avoids HashMap iteration nondeterminism; writes OUT_DIR/table.rs only after validation.
A, A0 accepted; empty, lowercase initial, underscore and Unicode variant names rejected. Empty table can emit unusable empty enums; no whole-table semantic completeness guarantee.
Table bytes B, variants V, forms F: parsing O(B+VĀ²) worst-case linear En::add membership plus expected hash operations; emitted bytes E retained O(B+F+E).
composition
Composition
En::canon/alt retain first form; variants retain first-seen order. main validates row arity, identifier, symbol uniqueness and class before forms; explicit characters claim slots before automatic text fallback. Fixed enum emission order avoids HashMap iteration nondeterminism; writes OUT_DIR/table.rs only after validation.
Build generates table enums consumed by parser dispatch and printers. Lexer tokens feed macros and parser; parser returns AST whose equality ignores spans. Printers and gate compare that quotient, not original bytes. Shared parent syntax backs scoped stages; stages are byte-bound projections, not independent Rust modules.
models
behavior_complement
Duplicate form acceptance and overwrite of the first canonical form are excluded for validated successful compilation.
reverse_reconstruction
Compatible inputs are tables with identical ordered variants, canonical first forms and lookup maps; comments, blank lines and redundant alternate canonical declarations can differ.
canonical_selection
First form is retained separately for canonical and infix/plain forms.
duplicate_precedence
Symbol identity and class checked before form duplication; references after whole pass.
generated_transport
SYM arrays share row order and enum discriminants; include in table.rs consumes matching arrays.
effect_boundary
Read table then validate and construct output, finally require OUT_DIR and write; errors panic without transaction guarantee.
tests
Evidence ā 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 ā https://md.groupants.elamur.ai/free/en/mova/latex/build.rs.groupant/