YAML frontmatter for R Markdown to cause rmarkdown::render() to retain intermediate Markdown file for .R and .Rmd files, respectively

rmd_yaml_variation1.yaml

---
type: post
title: "Data Wrangling"
subtitle: "For Stoat control in Beech forest paper"
author: "Anthony Davidson"
date: '2019-05-16'
output: rmarkdown::html_vignette
vignette: >
  %\VignetteIndexEntry{Vignette Title}
  %\VignetteEngine{knitr::rmarkdown}
  %\VignetteEncoding{UTF-8}:
bibliography: Beech-forests.bib
editor_options: 
  chunk_output_type: console
---

yaml_classi2.yaml

#html
#pretty_html styles
#version 1.0.1
---
  title: "Population dynamics of Mice in New Zealand Beech Forests"
author: "Anthony Davidson, University of Canberra"
date: '`r format(Sys.time(), "%d %B, %Y")`'
output:
  prettydoc::html_pretty:
  theme: cayman
highlight: github
vignette: >
  %\VignetteIndexEntry{Vignette Title}
%\VignetteEngine{knitr::rmarkdown}
%\VignetteEncoding{UTF-8}
---

yaml_classic.yaml

# ------.YMAL compile code------------
# Anthony Davidson
# 14012019
# At test of tests

#pdf classic .tex style
#version 1.0.1
---
  title: "Population dynamics of Mice in New Zealand Beech Forests"
author: "Anthony Davidson, University of Canberra"
date: '`r format(Sys.time(), "%d %B, %Y")`'
output:
  pdf_document:
  fig_caption: yes
keep_tex: yes
number_sections: yes
html_document:
  fig_caption: yes
force_captions: yes
highlight: pygments
number_sections: no
theme: cerulean
---

yaml_frontmatter_jekyll_post.yaml

---
title: "Something interesting"
subtitle: "A subnote"
layout: post
tags: ["general", "overview", "website"]
image: /img/
bigimg: /img/
permlink:
---

yaml_frontmatter_r_github_document.yaml

#' ---
#' title: "Something fascinating"
#' author: "Anthony Davidson"
#' date: "`r format(Sys.Date())`"
#' output: github_document
#' ---

yaml_frontmatter_r_keep_md.yml

#' ---
#' title: "Something fascinating"
#' author: "Anthony Davidson"
#' date: "`r format(Sys.Date())`"
#' output:
#'   html_document:
#'     keep_md: TRUE
#' ---

yaml_frontmatter_rmd_github_document.yaml

---
title: "Something fascinating"
author: "Anthony Davidson"
date: "`r format(Sys.Date())`"
output: github_document
---

yaml_frontmatter_rmd_keep_md.yml

---
title: "Something fascinating"
author: "Anthony Davidson"
date: "`r format(Sys.Date())`"
output:
  html_document:
    keep_md: TRUE
---