-if (require("knitr")) {
- if (packageVersion("knitr") < '1.9.19') {
+generate_md_episodes <- function() {
+
+ 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") && packageVersion("checkpoint") >= '0.4.0') {
+ required_pkgs <-
+ checkpoint:::scanForPackages(project = "_episodes_rmd",
+ verbose=FALSE, use.knitr = TRUE)$pkgs
+ } else {
+ stop("The checkpoint package (>= 0.4.0) is required to build the lessons.")
}
-} else stop("knitr 1.9.20 or above is needed to build the lessons.")
-if (!require("stringr"))
- stop("The package stringr is required for generating the lessons.")
+ missing_pkgs <- required_pkgs[!(required_pkgs %in% rownames(installed.packages()))]
-src_rmd <- list.files(pattern = "??-*.Rmd$", path = "_episodes_rmd", full.names = TRUE)
-dest_md <- file.path("_episodes", gsub("Rmd$", "md", basename(src_rmd)))
+ if (length(missing_pkgs)) {
+ message("Installing missing required packages: ",
+ paste(missing_pkgs, collapse=", "))
+ install.packages(missing_pkgs)
+ }
+
+ ## find all the Rmd files, and generate the paths for their respective outputs
+ src_rmd <- list.files(pattern = "??-*.Rmd$", path = "_episodes_rmd", full.names = TRUE)
+ dest_md <- file.path("_episodes", gsub("Rmd$", "md", basename(src_rmd)))
+
+ ## knit the Rmd into markdown
+ mapply(function(x, y) {
+ knitr::knit(x, output = y)
+ }, src_rmd, dest_md)
-for (i in seq_along(src_rmd)) {
- knitr::knit(src_rmd[i], output = dest_md[i])
}
+
+generate_md_episodes()