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name: effect-collections-datastructs description: Value-based data structures (Data.struct, tuple, array) and high-performance collections (Chunk, HashSet). Use for safe comparisons and pipelines. allowed-tools: Read, Grep, Glob, Edit, Write

Data Structures & Collections

Structural Equality

Copyimport { Data, Equal } from "effect"
const a = Data.struct({ id: 1, name: "A" })
const b = Data.struct({ id: 1, name: "A" })
Equal.equals(a, b) // true

Tuples & Arrays

Copyconst t = Data.tuple(1, "x")
const arr = Data.array([1,2,3])

Chunk

Copyimport { Chunk } from "effect"
const items = Chunk.fromIterable([1,2,3])

HashSet

Copyimport { HashSet } from "effect"
const set = HashSet.fromIterable([1,2,3])

Local Source Reference

CRITICAL: Search local Effect source before implementing

The full Effect source code is available at docs/effect-source/. Always search the actual implementation before writing Effect code.

Key Source Files

• Data: docs/effect-source/effect/src/Data.ts
• Chunk: docs/effect-source/effect/src/Chunk.ts
• HashSet: docs/effect-source/effect/src/HashSet.ts
• Equal: docs/effect-source/effect/src/Equal.ts

Example Searches

Copy# Find Data.struct and equality patterns
grep -F "Data.struct" docs/effect-source/effect/src/Data.ts
grep -F "Data.tuple" docs/effect-source/effect/src/Data.ts

# Find Chunk operations
grep -F "export" docs/effect-source/effect/src/Chunk.ts | grep -F "function"

# Study HashSet API
grep -F "export" docs/effect-source/effect/src/HashSet.ts | grep -F "function"

# Find Equal implementation
grep -F "equals" docs/effect-source/effect/src/Equal.ts

Workflow

1. Identify the collection API you need (e.g., Chunk, HashSet)
2. Search docs/effect-source/effect/src/ for the implementation
3. Study the types and available operations
4. Look at test files for usage examples
5. Write your code based on real implementations

Real source code > documentation > assumptions

References

• Agent Skills overview: https://www.anthropic.com/news/skills
• Skills guide: https://docs.claude.com/en/docs/claude-code/skills