Is there any way to "check" or "verify" a source code file in R when sourcing it ? For example, I have this function in a file "source.R"
MyFunction <- function(x)
{
print(x+y)
}
When sourcing "source.R", I would like to see some sort of warning : MyFunctions refers to an undefined object Y.
Any hints on how to check / verifiy R code ?
Cheers!
I use a function like this one for scanning all the functions in a file:
critic <- function(file) {
require(codetools)
tmp.env <- new.env()
sys.source(file, envir = tmp.env)
checkUsageEnv(tmp.env, all = TRUE)
}
Assuming source.R contains the definitions of two rather poorly written functions:
MyFunction <- function(x) {
print(x+y)
}
MyFunction2 <- function(x, z) {
a <- 10
x <- x + 1
print(x)
}
Here is the output:
critic("source.R")
# MyFunction: no visible binding for global variable ‘y’
# MyFunction2: local variable ‘a’ assigned but may not be used
# MyFunction2: parameter ‘x’ changed by assignment
# MyFunction2: parameter ‘z’ may not be used
You can use the codetools package in base R for that. And if you had your code in a package, it would tell you about this:
