Elamur Groupantsmlab-table-display
The groupant beside mlab/src/table.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 | symbolic source derived | invariant |
| descriptant | present | descriptant |
| invariant | partial | invariant |
| tests | partial bounded parent evidence | 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 |
display_cost | display_cost | partial source derived model | display_cost |
layout_transport | layout_transport | partial source derived model | layout_transport |
branch_relation | branch_relation | partial source derived model | branch_relation |
resource_cost | resource_cost | partial source derived model | resource_cost |
Model text
descriptant
mlab-table-display
cells_of formats by kind; format_body selects all rows <=30, otherwise head10 tail5, widths count Unicode chars and header. Text left aligns, others right; format_str_arr traverses column-major data into row text.
Epoch 2026-10-31: isolated source-bound fragment over bytes [15045,18136); includes no claim beyond this relation. Source hash 7af3a65aabe33226d39f741909fd08d74c3b3e43390417c64e617a10704ac26b.
approximant
display: forward relation
cells_of formats by kind; format_body selects all rows <=30, otherwise head10 tail5, widths count Unicode chars and header. Text left aligns, others right; format_str_arr traverses column-major data into row text.
Domain: Well-shaped public Table/Mat/StrArr, in-range zero-based internal indices, bounded i64 civil arithmetic. Malformed direct structs may panic.
Executable surrogate gap: no measured cheaper implementation with a useful scoped metric is supplied. Categorical/error/effect relations are exact obligations, not percent losses. Future numeric caps only1/2/5/10%.
invariant
display: invariant and cost
All cells generated before selection, so elision reduces output not source-format work.
Names and shown widths determine pad; trailing spaces stripped, four-space indent and three-space separators.
Scope-specific cost: O(all cell rendering bytes) memory/time before selecting displayed rows; output only head10+tail5 above30 rows.
models
behavior_complement
Elided output excludes reconstruction of hidden rows; nonfinite Date displays NaT and string None displays <missing>. No ANSI width guarantee.
reverse_reconstruction
Display string admits many matrices differing beyond precision, elided middle rows or real literal <missing> text.
display_cost
All cells generated before selection, so elision reduces output not source-format work.
layout_transport
Names and shown widths determine pad; trailing spaces stripped, four-space indent and three-space separators.
branch_relation
cells_of formats by kind; format_body selects all rows <=30, otherwise head10 tail5, widths count Unicode chars and header. Text left aligns, others right; format_str_arr traverses column-major data into row text.
resource_cost
O(all cell rendering bytes) memory/time before selecting displayed rows; output only head10+tail5 above30 rows.
tests
Evidence boundary
See ../tests.md for the actual selected source test and mutant. These tests sample the file, not every fragment branch. Elided output excludes reconstruction of hidden rows; nonfinite Date displays NaT and string None displays <missing>. No ANSI width guarantee. Other branches here are source-derived and unexecuted unless the parent test explicitly calls them.
This page in Markdown → https://md.groupants.elamur.ai/free/en/mova/mlab/src/table.rs.groupant/display.groupant/