Checks extension using
vld_string(x) && vld_subset(tools::file_ext(x), ext)
The user may want to use toupper() or tolower()
to ensure the case matches.
Value
The chk_ function throws an informative error if the test fails or
returns the original object if successful so it can used in pipes.
The vld_ function returns a flag indicating whether the test was met.
See also
For more details about the use of this function,
please read the article
vignette("chk-families").
