Writing-Function-with-the-tidyverse

Tweet-sourced resources

1. https://www.vishalkatti.com/posts/2021-07-17-programmingwithdplyr/
2. https://ayushbipinpatel.github.io/R-for-Data-Analysis/functions-and-functional-programming.html#1
3. https://dplyr.tidyverse.org/articles/programming.html
4. https://www.brodrigues.co/blog/2019-06-20-tidy_eval_saga/
5. https://speakerdeck.com/chendaniely/learning-tidy-evaluation-by-reimplementing-dplyr
6. https://speakerdeck.com/jennybc/tidy-eval-in-context?slide=1
7. https://rlang.r-lib.org/
8. https://laderast.github.io/posts/2017-12-19-understanding-tidyeval/

Tidy Evaluation at Open Study Group

Section 1: Build a function that uses tidyverse unquoted args internally (LAVERY)

• Passing strings to dplyr verbs
• across() and any_of() and all_of()
• .data[[varname]] (also introduce .env pronoun)
• rlang::sym() and rlang::syms(), e.g. select(!!rlang::sym(varname))

Let’s build a function that creates a ggplot….maybe a survival curve?

Section 2: Build a function that uses unquoted args itself (SJOBERG)

• {{ }}
• First, easy option is to just immediately convert unquoted variable names to strings
• varname <- dplyr::select(data, {{ varname }}) |> names()
• enquo() and bang-bang (!!)

Recreate dplyr::select()

40 minutes of instruction 20 minutes of practice (stay on the line if you’re interested) Instruction will focus on section 1 skills

Xaringan slides will live in epi/bio gh org