How to keep the merged Rmd file created during Merge and Knit

问题

bookdown merges all of the Rmd files into one, before knitting, but deletes this files at the end of the process.

I would like to examine the merged Rmd for debugging purposes. How can I tell bookdown not keep this intermediate file instead of erasing it?

Update

I found out about the delete_merged_file option in _bookdown.yml, but unfortunately, it seems to have no effect.

来源：https://stackoverflow.com/questions/56031857/how-to-keep-the-merged-rmd-file-created-during-merge-and-knit