R roxygen2 Error in preref.parsers[[tag]] %||% parse.unknown: attempt to use zero-length variable name -

i intend use roxygen2 roxygenize() update package documentation after bit of work. have done in past. on instance encountered following error message:

==> roxygenize('.', roclets=c('rd', 'collate', 'namespace'))  * checking changes ... error  error in preref.parsers[[tag]] %||% parse.unknown :    attempt use zero-length variable name 

i don't doubt have problem variable name somewhere, though don't know how locate source of error.

r cmd check doesn't identify problems other collate , namespace issues mean use roxygen2 rectify...

any appreciated.

to track problem down systematically removed files , re-ran roxygenize() until no longer failed run through.

having identified offending file, suggested, misplaced "@".

this results in aforementioned error:

#' @ export 

so fix misplaced space , problem solved:

#' @export 

the difficult aspect locating typo.