knitr (version 1.10.5)

rand_seed: An unevaluated expression to return .Random.seed if exists

Description

This expression returns .Random.seed when eval(rand_seed) and NULL otherwise.

Usage

rand_seed

format

language { .GlobalEnv$.Random.seed }

Details

It is designed to work with opts_chunk$set(cache.extra = rand_seed) for reproducibility of chunks that involve with random number generation. See references.

References

http://yihui.name/knitr/demo/cache/

Examples

eval(rand_seed)
rnorm(1)  # .Random.seed is created (or modified)
eval(rand_seed)