diff --git a/README.Rmd b/README.Rmd new file mode 100644 index 0000000..70fac45 --- /dev/null +++ b/README.Rmd @@ -0,0 +1,85 @@ +--- +output: + github_document: + toc: true + toc_depth: 4 +--- + + + +```{r, echo = FALSE} +knitr::opts_chunk$set(collapse = TRUE, comment = "#>") +``` + +# Ode to the here package + +## TL;DR + +Install [here](https://krlmlr.github.io/here/). + +```{r eval = FALSE} +## install.packages(devtools) +devtools::install_github("krlmlr/here") +``` + +Use it. + +```{r eval = FALSE} +library(here) +here("data", "file_i_want.csv") +``` + +This works, regardless of where the associated source file lives inside your project. These paths will also "just work" during interactive development, without incessant fiddling with the working directory of your IDE's R process. + +`here::here()` works like `file.path()`, but where the path root is implicitly set to "the path to the top-level of my current project". See [The Fine Print](#the-fine-print) for the underlying heuristics. If they don't suit, use the more powerful package [rprojroot](https://krlmlr.github.io/rprojroot/) directly. Both [here](https://krlmlr.github.io/here/) and [rprojroot](https://krlmlr.github.io/rprojroot/) are written by [Kirill Müller](https://github.com/krlmlr) and rprojroot is already on CRAN. + +## Admitting you have a problem + +> If the first line of your #rstats script is `setwd("C:\Users\jenny\path\that\only\I\have")`, I will come into your lab and SET YOUR COMPUTER ON FIRE. + +Mash-up of rage tweets by [\@jennybc](https://twitter.com/JennyBryan/status/673240213313851393) and [\@tpoi](https://twitter.com/tpoi/status/720340395901648897). + +Do you: + + * Have `setwd()` in your scripts? PLEASE STOP DOING THAT. + - This makes your script very fragile, hard-wired to exactly one time and place. As soon as you rename or move directories, it breaks. Or maybe you get a new computer? Or maybe someone else needs to run your code? We show a very accessible way to go cold turkey and eliminate the `setwd()` gotcha from your code. + * Fanny around with working directory alot? During development and/or at run time? YOU CAN STOP DOING THAT TOO. + - Classic problem presentation: Awkwardness around building paths and/or setting working directory in projects with subdirectories. Especially if you use R Markdown and knitr, which trips up alot of people with its default behavior of "working directory = directory where this file lives". We show a very accessible way to specify paths in your project's `.R` and `.Rmd` files, regardless of where they live. + +## Actual demonstration + +I will let this code run. + +What does here think the top-level of current project is? The package displays this on load or, at any time, you can just call `here()`. + +```{r} +library(here) +here() +``` + +Build a path to something in a subdirectory and use it. + +```{r} +here("one", "two", "awesome.txt") +cat(readLines(here("one", "two", "awesome.txt"))) +``` + +Don't try this at home, folks! But let me set working directory to a subdirectory and prove to you that the same code as above, for getting the path to `awesome.txt`, still works. + +```{r} +setwd(here("one")) +getwd() +cat(readLines(here("one", "two", "awesome.txt"))) +``` + +## The fine print + +`here::here()` figures out the top-level of your current project using some sane heuristics. It looks at working directory, checks a criterion and, if not satisfied, moves up to parent directory and checks again. Lather, rinse, repeat. + +Here are the criteria, in order of precedence: + + * Is this an RStudio Project? Literally, can I find a file named something like `foo.Rproj`? + * Is this an R package? Does it have a `DESCRIPTION` file? + * Is this a [remake](https://github.com/richfitz/remake#readme) project? Does it have a file named `remake.yml`? + +The fallback position is to build path relative to current working directory. diff --git a/README.md b/README.md new file mode 100644 index 0000000..0062e30 --- /dev/null +++ b/README.md @@ -0,0 +1,91 @@ + +- [Ode to the here package](#ode-to-the-here-package) + - [TL;DR](#tldr) + - [Admitting you have a problem](#admitting-you-have-a-problem) + - [Actual demonstration](#actual-demonstration) + - [The fine print](#the-fine-print) + + +Ode to the here package +======================= + +TL;DR +----- + +Install [here](https://krlmlr.github.io/here/). + +``` r +## install.packages(devtools) +devtools::install_github("krlmlr/here") +``` + +Use it. + +``` r +library(here) +here("data", "file_i_want.csv") +``` + +This works, regardless of where the associated source file lives inside your project. These paths will also "just work" during interactive development, without incessant fiddling with the working directory of your IDE's R process. + +`here::here()` works like `file.path()`, but where the path root is implicitly set to "the path to the top-level of my current project". See [The Fine Print](#the-fine-print) for the underlying heuristics. If they don't suit, use the more powerful package [rprojroot](https://krlmlr.github.io/rprojroot/) directly. Both [here](https://krlmlr.github.io/here/) and [rprojroot](https://krlmlr.github.io/rprojroot/) are written by [Kirill Müller](https://github.com/krlmlr) and rprojroot is already on CRAN. + +Admitting you have a problem +---------------------------- + +> If the first line of your \#rstats script is `setwd("C:\Users\jenny\path\that\only\I\have")`, I will come into your lab and SET YOUR COMPUTER ON FIRE. + +Mash-up of rage tweets by [@jennybc](https://twitter.com/JennyBryan/status/673240213313851393) and [@tpoi](https://twitter.com/tpoi/status/720340395901648897). + +Do you: + +- Have `setwd()` in your scripts? PLEASE STOP DOING THAT. +- This makes your script very fragile, hard-wired to exactly one time and place. As soon as you rename or move directories, it breaks. Or maybe you get a new computer? Or maybe someone else needs to run your code? We show a very accessible way to go cold turkey and eliminate the `setwd()` gotcha from your code. +- Fanny around with working directory alot? During development and/or at run time? YOU CAN STOP DOING THAT TOO. +- Classic problem presentation: Awkwardness around building paths and/or setting working directory in projects with subdirectories. Especially if you use R Markdown and knitr, which trips up alot of people with its default behavior of "working directory = directory where this file lives". We show a very accessible way to specify paths in your project's `.R` and `.Rmd` files, regardless of where they live. + +Actual demonstration +-------------------- + +I will let this code run. + +What does here think the top-level of current project is? The package displays this on load or, at any time, you can just call `here()`. + +``` r +library(here) +#> here() starts at /Users/jenny/rrr/here_here +here() +#> [1] "/Users/jenny/rrr/here_here" +``` + +Build a path to something in a subdirectory and use it. + +``` r +here("one", "two", "awesome.txt") +#> [1] "/Users/jenny/rrr/here_here/one/two/awesome.txt" +cat(readLines(here("one", "two", "awesome.txt"))) +#> OMG this is so awesome! +``` + +Don't try this at home, folks! But let me set working directory to a subdirectory and prove to you that the same code as above, for getting the path to `awesome.txt`, still works. + +``` r +setwd(here("one")) +getwd() +#> [1] "/Users/jenny/rrr/here_here/one" +cat(readLines(here("one", "two", "awesome.txt"))) +#> OMG this is so awesome! +``` + +The fine print +-------------- + +`here::here()` figures out the top-level of your current project using some sane heuristics. It looks at working directory, checks a criterion and, if not satisfied, moves up to parent directory and checks again. Lather, rinse, repeat. + +Here are the criteria, in order of precedence: + +- Is this an RStudio Project? Literally, can I find a file named something like `foo.Rproj`? +- Is this an R package? Does it have a `DESCRIPTION` file? +- Is this a [remake](https://github.com/richfitz/remake#readme) project? Does it have a file named `remake.yml`? + +The fallback position is to build path relative to current working directory. diff --git a/one/two/awesome.txt b/one/two/awesome.txt new file mode 100644 index 0000000..52b3da9 --- /dev/null +++ b/one/two/awesome.txt @@ -0,0 +1 @@ +OMG this is so awesome!