R/zzz.R

In Dasonk/future: Imports functions from future versions of R

.onLoad <- function(libname, pkgname){
    major <- as.numeric(sessionInfo()$R.version$major)
    minor <- as.numeric(sessionInfo()$R.version$minor)
    message <- paste("Your version of R is: ", 
                     major, 
                     ".", 
                     minor, 
                     "\nTo get the most out of future please install:",
                     sep = "")
    
    loadAndMessage <- function(package){
        inst <- suppressWarnings(require(package, character.only=TRUE, quietly=TRUE))
        if(!inst){
            message <<- c(message, package)
        }
    }
    
    if(major == 2){
        if(minor < 14){
            loadAndMessage("future2.14")
        }
        if(minor < 15){
            loadAndMessage("future2.15")
        }
        
        # Need 3.0
        loadAndMessage("future3.0")
    }
    # If major = 3.0 then they're on developmental version... 
    # no worries about that for now...
    
    if(length(message) > 1){
        message <- c(message, 
                     "\nYou can call installFuture() to do this for you automatically")
        packageStartupMessage(paste(message, collapse ="\n"))

    }
}