.Rbuildignore has a regular expression on each line, but it's
usually easier to work with specific file names. By default,
use_build_ignore() will (crudely) turn a filename into a regular
expression that will only match that path. Repeated entries will be
silently removed.
use_build_ignore() is designed to ignore individual files. If you
want to ignore all files with a given extension, consider providing
an "as-is" regular expression, using escape = FALSE; see examples.
use_build_ignore(files, escape = TRUE)Character vector of path names.
If TRUE, the default, will escape . to
\\. and surround with ^ and $.
if (FALSE) {
# ignore all Excel files
use_build_ignore("[.]xlsx$", escape = FALSE)
}