---
slug: "Select"
name: "Select"
type: "Primitives"
layer: "Infrastructure"
ref: "Select#decf"
sema_id: "sema:Select#mh:SHA-256:decf9c05490dc5e6b372c5dbb7d89d2285fdd832714fc992b10fdbd6b7c2c2e3"
tags: ["Infrastructure","Primitives"]
updated: 2026-11-11
mindscape: "bootstrap"
index_url: https://mindscape.world/scapes/bootstrap.json
url: https://mindscape.world/bootstrap/Select/
related: ["Act","Ballot","BeamSearch","Card","DataMinimization","Decision","OODA","Rally","Rank"]
---

# Select

Generic selection of items from a set based on criteria

Layer: Infrastructure · Category: Primitives

## Mechanism

Deterministic Filter. Applies a Predicate Function P(x) to every element in Input Set S. Returns a new Subset S' containing only elements where P(x) is True. It filters a set based on specific inclusion criteria.

## Invariants

- Predicate Truth: For all x in Output, Criterion(x) must be True.
- Subset Property: Output must be a subset of Input (no new items created).
- Determinism: Same input set + same criteria = same output set.

## Preconditions

- Criterion is decidable for item type
- Input set is iterable

## Postconditions

- Subset returned

## Failure modes

- Empty Result: No items satisfy the criterion (returns empty set).
- Predicate Error: The criterion function fails or throws an error for specific inputs.

## Parameters

- `limit` (Integer, [1, 10000]): Max items to return
- `strategy` (Enum, {Filter, First}): Default: Filter. Random sampling is excluded — it would violate the Determinism invariant.

## Builds on

—

## Used by

- [Act](https://mindscape.world/scapes/bootstrap/Act.md) (Infrastructure; References)
- [Ballot](https://mindscape.world/scapes/bootstrap/Ballot.md) (Infrastructure; References)
- [BeamSearch](https://mindscape.world/scapes/bootstrap/BeamSearch.md) (Mind; References)
- [Card](https://mindscape.world/scapes/bootstrap/Card.md) (Infrastructure; Composes with)
- [DataMinimization](https://mindscape.world/scapes/bootstrap/DataMinimization.md) (Society; References)
- [Decision](https://mindscape.world/scapes/bootstrap/Decision.md) (Infrastructure; References)
- [OODA](https://mindscape.world/scapes/bootstrap/OODA.md) (Mind; Composes with)
- [Rally](https://mindscape.world/scapes/bootstrap/Rally.md) (Society; Composes with)
- [Rank](https://mindscape.world/scapes/bootstrap/Rank.md) (Infrastructure; Composes with)

## Identity

- Sema ID: `sema:Select#mh:SHA-256:decf9c05490dc5e6b372c5dbb7d89d2285fdd832714fc992b10fdbd6b7c2c2e3`
- Ref: `Select#decf`
- Supersedes:
  - `sema:Select#mh:SHA-256:2fa0da3874e2a9a2c8664ed919d03c28a1f6b76daf9621f069d1ca1cb18a64b6`

## Links

- [Pattern page](https://mindscape.world/bootstrap/Select/)
- [View in the interactive graph](https://mindscape.world/bootstrap/#Select)
- [JSON](https://mindscape.world/scapes/bootstrap/Select.json)
- [Index of all patterns](https://mindscape.world/scapes/bootstrap.json)