CodeSampleX

Sample

map string index offset to line and column location and index for location

sha256:0102bb8ffef38a61c81460b46dd47e1be569f701ff072f1500af5f6369bffb4c

This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured. How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people. MIT-0

Execution evidence

The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.

Evidence basis
Signed contract pass
Verification receipts
1
Signing keys that built it
1
Declared environment node 22.23 linux 24 · ubuntu · glibc 2.39 x64 node 22.23 javascript npm 10

Verification-run environments

Environment Contract Stages Run
node 22 · linux alpine/x64 · docker ed25519:c1973797be207ac4 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · node-typescript@1node:22-alpine@sha256:c610fcdfb1d5…
2026-08-23

Case

HOW
Goal
map string index offset to line and column location and index for location
Packages
Symbols
  • LinesAndColumns
  • LinesAndColumns.indexForLocation
  • LinesAndColumns.locationForIndex
Environment
node 22.23.2
Created
2026-08-23T15:26:05Z

Contract

  1. assert LinesAndColumns.locationForIndex maps 0-based character offset to { line, column } location
  2. assert LinesAndColumns.locationForIndex returns null for negative offset or offset beyond string length
  3. assert LinesAndColumns.indexForLocation maps { line, column } location to character offset
  4. assert LinesAndColumns.indexForLocation returns null for out-of-bounds line or column
  5. assert LinesAndColumns handles LF, CR, and CRLF line endings with round-trip location-to-index fidelity

Files

  • PROMPT.md
  • csx.json
  • index.js
  • package-lock.json
  • package.json
  • spec.json
  • test/contract.mjs

Download the source artifact (tar.gz)

Origin Seeder

anonymous