Only cleaning intermediate R files on demand.

	@find . -name .DS_Store -exec rm {} \;

	@find . -name '*~' -exec rm {} \;

	@find . -name '*.pyc' -exec rm {} \;

## clean-rmd      : clean intermediate R files (that need to be committed to the repo).

clear-rmd :

	@rm -rf ${RMD_DST}

	@rm -rf fig/swc-rmd-*

	@rm -rf fig/rmd-*

## ----------------------------------------

## Commands specific to workshop websites.

fix_fig_path <- function(pth) file.path("..", pth)

## We use the swc-rmd- prefix for the figures generated by the lssons

## so they can be easily identified and deleted by `make clean`.  The

## We use the rmd- prefix for the figures generated by the lssons so

## they can be easily identified and deleted by `make clean-rmd`.  The

## working directory when the lessons are generated is the root so the

## figures need to be saved in fig/, but when the site is generated,

## the episodes will be one level down. We fix the path using the

## `fig.process` option.

opts_chunk$set(tidy = FALSE, results = "markup", comment = NA,

               fig.align = "center", fig.path = "fig/swc-rmd-",

               fig.align = "center", fig.path = "fig/rmd-",

               fig.process = fix_fig_path)

# The hooks below add html tags to the code chunks and their output so that they

# are properly formatted when the site is built.

hook_in <- function(x, options) {

  stringr::str_c("\n\n~~~\n",

                 paste0(x, collapse="\n"),