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@hrbrmstr /ghelp.R
Last active Aug 29, 2015

What would you like to do?
github search in rstudio viewer pane - source it and try it with ghelp("vapply")
ghelp <- function(topic, in_cran=TRUE) {
require(htmltools) # for getting HTML to the viewer
require(rvest) # for scraping & munging HTML
# github search URL base
base_ext_url <- ""
ext_url <- sprintf(base_ext_url, topic)
# if searching with user:cran (the default) add that to the URL
if (in_cran) ext_url <- paste(ext_url, "+user%3Acran", sep="", collapse="")
# at the time of writing, "rvest" and "xml2" are undergoing some changes, so
# accommodate those of us who are on the bleeding edge of the hadleyverse
# either way, we are just extracting out the results <div> for viewing in
# the viewer pane (it works in plain ol' R, too)
if (packageVersion("rvest") < "") {
pg <- html(ext_url)
res_div <- paste(capture.output(html_node(pg, "div#code_search_results")), collapse="")
} else {
pg <- read_html(ext_url)
res_div <- as.character(html_nodes(pg, "div#code_search_results"))
# clean up the HTML a bit
res_div <- gsub('How are these search results\\? <a href="/contact">Tell us!</a>', '', res_div)
# include a link to the results at the top of the viewer
res_div <- gsub('href="/', 'href="', res_div)
# build the viewer page, getting CSS from github-proper and hiding some cruft
for_view <- sprintf('<html><head><link crossorigin="anonymous" href="" media="all" rel="stylesheet" /><style>body{padding:20px}</style></head><body><a href="%s">Show on GitHub</a><hr noshade size=1/>%s</body></html>', ext_url, res_div)
# this makes it show in the viewer (or browser if you're using plain R)
Error in UseMethod("html_nodes") : 
  no applicable method for 'html_nodes' applied to an object of class "c('xml_document', 'xml_node')"

:\ Have you seen that error?

P.S. My machine has:

    Package Version
1      xml2   0.1.1
2     rvest   0.2.0
3 htmltools   0.2.6

hrbrmstr commented Jun 29, 2015

aye. i just made a note in the source.

rvest * 2015-06-21 Github (hadley/rvest@9461bc4) is what I'm using. I think i can tweak this, tho.


hrbrmstr commented Jun 29, 2015

and, it should work on stable and github versions

I think you want xml2, not xml


hrbrmstr commented Jun 29, 2015

aye. thxk @cpsievert. v1 was beautiful. v2+ has been coded whilst catching up from being on vacation and dealing with the morning routine.

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