1 / 38

Artwork by @allison_horst

2 / 38

3 / 38

4 / 38

Even the creator of R Markdown and knitr isn't crazy about YAML

5 / 38

YAML:Yet Another Markup LanguageYAML Ain't Markup Language6 / 38

7 / 38

8 / 38

9 / 38

10 / 38

11 / 38

library(ymlthis)
as_yml(
"title: Annual Report
author: Malcolm Barrett
date: '`r Sys.Date()`'
output:
  pdf_document:
    toc: true
"
) %>% draw_yml_tree()

12 / 38

library(ymlthis)
as_yml(
"title: Annual Report
author: Malcolm Barrett
date: '`r Sys.Date()`'
output:
  pdf_document:
    toc: true
"
) %>% draw_yml_tree()

13 / 38

library(ymlthis)
as_yml(
"title: Annual Report
author: Malcolm Barrett
date: '`r Sys.Date()`'
output:
  pdf_document:
    toc: true
"
) %>% draw_yml_tree()

├── title: Annual Report
├── author: Malcolm Barrett
├── date: '`r Sys.Date()`'
└── output:
     └── pdf_document:
         └── toc: true

14 / 38

⚠️ YAML fails silently

15 / 38

Introducing ymlthis16 / 38

Introducing ymlthis✔️ Write YAML17 / 38

Introducing ymlthis✔️ Write YAML✔️ Document YAML18 / 38

Introducing ymlthis✔️ Write YAML✔️ Document YAML✔️ Improve R Markdown Workflows19 / 38

Introducing ymlthis✔️ Write YAML✔️ Document YAML✔️ Improve R Markdown Workflows📥 Validation20 / 38

Writing YAML

yml()

21 / 38

Writing YAML

yml()

---
author: Malcolm Barrett
date: '`r format(Sys.Date())`'
---

22 / 38

Writing YAML

yml() %>% 
  yml_output(
    pdf_document(toc = TRUE),
    html_document()
  )

23 / 38

Writing YAML

yml() %>% 
  yml_output(
    pdf_document(toc = TRUE),
    html_document()
  )

---
author: Malcolm Barrett
date: '`r format(Sys.Date())`'
output:
   pdf_document:
     toc: true
  html_document: default
---

24 / 38

Writing YAML

yml() %>%
  yml_author(
    c("Yihui Xie", "Hadley Wickham"),
    affiliation = "RStudio"
  ) %>%
  yml_date("07/04/2019") %>%
  yml_title("Reproducible Research in R") %>% 
  yml_category(c("r", "reprodicibility")) %>%
  yml_output(
    pdf_document(
      keep_tex = TRUE,
      includes = includes2(after_body = "footer.tex")
    )
  ) %>%
  yml_latex_opts(biblio_style = "apalike")

25 / 38

Writing YAML

---
author:
- name: Yihui Xie
   affiliation: RStudio
- name: Hadley Wickham
   affiliation: RStudio
date: 07/04/2019
title: Reproducible Research in R
category:
- r
- reprodicibility
output:
  pdf_document:
    keep_tex: true
    includes:
      after_body: footer.tex
biblio-style: apalike
---

26 / 38

R Markdown Extensions

package
output function
top-level YAML


bookdown
✓
✓

blogdown
✓
✓

pkgdown
✓
✓

pagedown
✓
✓

rticles
✓
✓

distill
✓
✓

learnr
✓
✗

xaringan
✓
✗

revealjs
✓
✗

flexdashboard
✓
✗


27 / 38

package	output function	top-level YAML
bookdown	✓	✓
blogdown	✓	✓
pkgdown	✓	✓
pagedown	✓	✓
rticles	✓	✓
distill	✓	✓
learnr	✓	✗
xaringan	✓	✗
revealjs	✓	✗
flexdashboard	✓	✗

Documenting YAML?yml_*()28 / 38

Image by @dataandme

29 / 38

30 / 38

Improving R Markdown Workflows

`use_yml()`

yml() %>%
  use_yml()

  ---
  author: Malcolm Barrett
  date: '`r format(Sys.Date())`'
  ---
● Paste into R Markdown or YAML file

# Places YAML on your cliboard

31 / 38

Improving R Markdown Workflows

`use_rmarkdown()`

yml() %>%
  use_rmarkdown()
# opens a new R Markdown file

32 / 38

Improving R Markdown Workflows

bookdown_yaml <- yml() %>% yml_output(bookdown::pdf_document2())
use_yml_defaults(bookdown_yaml)

33 / 38

Improving R Markdown Workflows

bookdown_yaml <- yml() %>% yml_output(bookdown::pdf_document2())
use_yml_defaults(bookdown_yaml)

   options(ymlthis.default_yml = "author: Malcolm Barrett
   date: '`r format(Sys.Date())`'
   output: bookdown::pdf_document2")
● Run interactively or paste into .Rprofile (perhaps using `usethis::edit_r_profile()`)

34 / 38

Improving R Markdown Workflows

bookdown_yaml <- yml() %>% yml_output(bookdown::pdf_document2())
use_yml_defaults(bookdown_yaml)

  options(ymlthis.default_yml = "author: Malcolm Barrett
  date: '`r format(Sys.Date())`'
  output: bookdown::pdf_document2")
● Run interactively or paste into .Rprofile (perhaps using `usethis::edit_r_profile()`)

use_rmarkdown()

35 / 38

Write to .Rmd files

function
action


use_rmarkdown()
Write yml to a .Rmd file

use_index_rmd()
Write yml to Index.Rmd

Write to .yml files

function
action


use_yml_file()
Write yml to a file

use_bookdown_yml()
Write yml to _bookdown.yml

use_navbar_yml()
Write yml to _navbar.yml

use_output_yml()
Write yml to _output.yml

use_pkgdown_yml()
Write yml to _pkgdown.yml

use_site_yml()
Write yml to _site.yml

36 / 38

function	action
`use_rmarkdown()`	Write `yml` to a `.Rmd` file
`use_index_rmd()`	Write `yml` to `Index.Rmd`

function	action
`use_yml_file()`	Write `yml` to a file
`use_bookdown_yml()`	Write `yml` to `_bookdown.yml`
`use_navbar_yml()`	Write `yml` to `_navbar.yml`
`use_output_yml()`	Write `yml` to `_output.yml`
`use_pkgdown_yml()`	Write `yml` to `_pkgdown.yml`
`use_site_yml()`	Write `yml` to `_site.yml`

visit the site for tutorials and documentation

http://ymlthis.r-lib.org

37 / 38

malcolmbarrett

@malco_barrett

Slides created via the R package xaringan.

38 / 38

Help

Keyboard shortcuts

↑, ←, Pg Up, k

Go to previous slide

↓, →, Pg Dn, Space, j

Go to next slide

Home

Go to first slide

End

Go to last slide

Number + Return

Go to specific slide

b / m / f

Toggle blackout / mirrored / fullscreen mode

Clone slideshow

Toggle presenter mode

Restart the presentation timer

?, h

Toggle this help