modify the imported version of a function
Figured it out...in case it is useful to others:
> library(lint)
> lint.enclos <- parent.env(asNamespace("lint"))
> stopifnot(all(c("perl", "regex") %in% ls(lint.enclos)))
> lint.enclos$perl
function (pattern)
{
message("perl is deprecated. Please use regexp instead")
regex(pattern)
}
<environment: namespace:stringr>
> unlockBinding("perl", lint.enclos)
> lint.enclos$perl <- lint.enclos$regex
> lint.enclos$perl
function (pattern, ignore_case = FALSE, multiline = FALSE, comments
= FALSE,
dotall = FALSE, ...)
{
options <- stri_opts_regex(case_insensitive = ignore_case,
multiline = multiline, comments = comments, dotall = dotall,
...)
structure(pattern, options = options, class = c("regex",
"pattern", "character"))
}
<environment: namespace:stringr>
On 12/16/2016 06:06 PM, Benjamin Tyner wrote:
Hi I saw on the assignInNamespace help page, that it changes "the copy in the namespace, but not any copies already exported from the namespace, in particular an object of that name in the package (if already attached) and any copies already imported into other namespaces." So now I'm wondering, whether there is a way to modify such copies already imported into other namespaces? For a concrete example, consider the lint package (now archived on CRAN) which includes a function check_pattern, which calls stringr:::perl, which has been deprecated in newer versions:
> stringr:::perl
function (pattern)
{
message("perl is deprecated. Please use regexp instead")
regex(pattern)
}
<environment: namespace:stringr>
so, what if I wanted to directly replace stringr:::perl with
stringr:::regex, in such a way that lint::check_pattern sees the
replacement? Is there a way, preferably without having to attach
stringr to the search path?
(I'm mostly just interested in learning about how namespace imports
actually work; of course in this toy example one could use
suppressMessages to hide that deprecation message).
Regards
Ben