The following function gives all the structures of an object in R. This function (plus dput()/str() for object attributes) fully qualifies everything about an arbitrary R object.
ObjectStructure <- function(x, ShowAll=FALSE) {
op <- options("warn")
options(warn=-1) # Assign "-1" to warn option to temporarily close warnings
on.exit(options(op)) # Reset the settings to initial ones after exit from the ObjectStructure function
is.Functions <- grep(methods(is), pattern="<-", invert=TRUE, value=TRUE) # 55 (is.X) functions
isDotlessFunctions <- character()
packs <- c('base', 'utils', 'methods') # include more packages if needed
for (pkg in packs) {
library(pkg, character.only = TRUE)
objects <- grep("^is.+\\w$", ls(envir=as.environment(paste('package', pkg, sep=':'))), value=TRUE)
objects <- grep("<-", objects, invert=TRUE, value=TRUE)
if (length(objects) > 0)
isDotlessFunctions <- append(isDotlessFunctions, objects[sapply(objects, function(x) class(eval(parse(text=x))) == "function")])
}
FunctionsList <- union(is.Functions, isDotlessFunctions)
result <- data.frame(test=character(), value=character(), warn=character(), stringsAsFactors=FALSE)
# Loop all the "is.(...)" functions and save the results
for(islev in FunctionsList) {
res <- try(eval(call(islev,x)),silent=TRUE) # In cases of error, let error be processed
# in errored cases, try produces try-error object that contains error message
if(class(res)=="try-error") { next() # In case of error, ignore current iteration and pass to the next iteration in the loop
} else if (length(res)>1) {
warn <- "*Applies only to the first element of the provided object"
value <- paste(res,"*",sep="")
} else {
warn <- ""
value <- res
}
result[nrow(result)+1,] <- list(islev, value, warn)
}
result <- result[order(result$value, decreasing=TRUE),] # Order the results
rownames(result) <- NULL # to arrange row numbers in a way that they start from 1 and ordered
if(ShowAll) return(result) # Show only the structures that give TRUE
else return(result[which(result$value=="TRUE"),]) # All the function results that give a TRUE/FALSE value
}
ObjectStructure(1L, TRUE) # See how the function works
As the user @dominic-comtois emphasize here, more packages can be included in packs variable. So,
What are the packages that include internal is.X (is.vector, is.numeric, etc.) and all isX (isS4, isOpen etc.) functions in general?
