R/RGhelp.R

In DiegoZardetto/ReGenesees.GUI: GUI Facility for the ReGenesees Package

RGhelp <- function (lib.loc = NULL, verbose = getOption("verbose"),
                    try.all.packages = getOption("help.try.all.packages"))
############################################################
# A temporary trick to browse the ReGenesees 000Index html #
# page, without loosing links: works by actually kidding   #
# the utils package.                                       #
# NOTE: May reveal UNSTABLE if changes arise in utils!!!!  #
############################################################
{
# Pick a convenience topic surely belonging to ReGenesees help pages...
topic <- "e.svydesign"
# Specify the package to be sift...
package <- "ReGenesees"
# Choose html help: pdf and other cannot work by kidding utils...
help_type = "html"
# Then start kidding utils package...

    if (!missing(package))
        if (is.name(y <- substitute(package)))
            package <- as.character(y)
    if (missing(topic)) {
        if (!missing(package))
            return(library(help = package, lib.loc = lib.loc,
                character.only = TRUE))
        if (!missing(lib.loc))
            return(library(lib.loc = lib.loc))
        topic <- "help"
        package <- "utils"
        lib.loc <- .Library
    }
    ischar <- tryCatch(is.character(topic) && length(topic) ==
        1L, error = identity)
    if (inherits(ischar, "error"))
        ischar <- FALSE
    if (!ischar) {
        reserved <- c("TRUE", "FALSE", "NULL", "Inf", "NaN",
            "NA", "NA_integer_", "NA_real_", "NA_complex_", "NA_character_")
        stopic <- deparse(substitute(topic))
        if (!is.name(substitute(topic)) && !stopic %in% reserved)
            stop("'topic' should be a name, length-one character vector or reserved word")
        topic <- stopic
    }
    help_type <- if (!length(help_type))
        "text"
    else match.arg(tolower(help_type), c("text", "html", "postscript",
        "ps", "pdf"))
    # Here access index.search from utils (find.package is a new entry in package base...):
    paths <- utils_index.search(topic, find.package(package, lib.loc,
        verbose = verbose))
    tried_all_packages <- FALSE
    if (!length(paths) && is.logical(try.all.packages) && !is.na(try.all.packages) &&
        try.all.packages && missing(package) && missing(lib.loc)) {
        for (lib in .libPaths()) {
            packages <- .packages(TRUE, lib)
            packages <- packages[is.na(match(packages, .packages()))]
            paths <- c(paths, utils_index.search(topic, file.path(lib,
                packages)))
        }
        paths <- paths[paths != ""]
        tried_all_packages <- TRUE
    }
    paths <- unique(paths)
    attributes(paths) <- list(call = match.call(), topic = topic,
        tried_all_packages = tried_all_packages, type = help_type)

    # Kidding utils, acts here:
    paths[1] <- gsub("e.svydesign","00Index",paths[1])
    class(paths) <- "help_files_with_topic"
    # Note: MUST explicitly print, otherwise the html server doesn't start
    # when RGhelp is triggered by a GUI dialog...
#   paths
    print(paths)
}