Demonstrates R lint error. Run like this (need to make executable first, `chmod +x Rlint.R`): ./Rlint.R lint_test.R

lint_test.R

a = 1

Rlint.R

#!/usr/bin/env Rscript

try_require <- function(pkg){
    e <- try(
        suppressPackageStartupMessages(library(pkg,character.only=TRUE))
        ,silent=TRUE)
    if(class(e) == 'try-error')
        invisible(FALSE)
    else
        invisible(TRUE)
}

try_require_install <- function(pkg){
    if(!(result <- try_require(pkg))){
        install.packages(pkg,repos='http://cran.rstudio.com/',quiet=TRUE)
        result <- try_require(pkg)
    }
    invisible(result)
}

installed <- c(
    try_require_install('optparse'),
    try_require_install('lint')
    )
if(any(!installed)){
    cat('Could not install optparse or lint packages.\n')
    q(status=1)
}


op.obj <- OptionParser()
opt <- parse_args(op.obj, positional_arguments = TRUE)

file <- opt$args
opt <- opt$options

if(length(file) == 0) { 
    cat('No input file.\n')
    q(status=1) 
}else if(length(file) > 1){
    cat('Too many input files.\n')
    q(status=1)
}

l <- lint(file)