generate_md_episodes <- function() {
- if (require("knitr")) {
- if (packageVersion("knitr") < '1.9.19') {
- stop("knitr must be version 1.9.20 or higher")
- }
- } else stop("knitr 1.9.20 or above is needed to build the lessons.")
+ if (require("knitr") && packageVersion("knitr") < '1.9.19')
+ stop("knitr must be version 1.9.20 or higher")
if (!require("stringr"))
stop("The package stringr is required for generating the lessons.")
+ if (require("checkpoint")) {
+ required_pkgs <-
+ checkpoint:::projectScanPackages(project = "_episodes_rmd",
+ verbose=FALSE, use.knitr = TRUE)$pkgs
+ } else {
+ stop("The checkpoint package is required to build the lessons.")
+ }
+
+ missing_pkgs <- required_pkgs[!(required_pkgs %in% rownames(installed.packages()))]
+
+ if (length(missing_pkgs)) {
+ message("Installing missing required packages: ",
+ paste(missing_pkgs, collapse=", "))
+ install.packages(missing_pkgs)
+ }
+
## find all the Rmd files, and generates the paths for their respective outputs
src_rmd <- list.files(pattern = "??-*.Rmd$", path = "_episodes_rmd", full.names = TRUE)
dest_md <- file.path("_episodes", gsub("Rmd$", "md", basename(src_rmd)))