register_kernel: Register a shard kernel

In shard: Deterministic, Zero-Copy Parallel Execution for R

Register a shard kernel

Description

Registers a named kernel implementation that can be selected by shard_map(..., kernel = "name").

Usage

register_kernel(
  name,
  impl,
  signature = NULL,
  footprint = NULL,
  supports_views = TRUE,
  description = NULL
)

Arguments

name	Kernel name (string).
impl	Function implementing the kernel. It must accept the shard descriptor as its first argument.
signature	Optional short signature string for documentation.
footprint	Optional footprint hint. Either a constant (bytes) or a function ⁠(shard, ...) -> list(class='tiny'|'medium'|'huge', bytes=...)⁠.
supports_views	Logical. Whether the kernel is intended to operate on shard views without slice materialization.
description	Optional human-readable description.

Details

A "kernel" is just a function that shard_map can call for each shard. The registry lets shard_map attach additional metadata (footprint hints, supports_views) for scheduling/autotuning.

Value

Invisibly, the registered kernel metadata.

Examples

list_kernels()

shard documentation built on April 3, 2026, 9:08 a.m.