Quasiquotation of R is terrible.

quasiquotation_metaprogramming.R

#!/usr/bin/env Rscript
# -*- coding: utf-8 -*-
#
# Copyright © 2020 Ye Chang <yech1990@gmail.com>
# Distributed under terms of the MIT license.
#
# Created: 2020-04-07 14:27


f <- function(x) {
    print(x)
}

rev_f <- function(x) {
    if (is.name(substitute(x))) {
        print(as.character(substitute(x)))
    } else {
        print(eval(as.name(x), envir = .GlobalEnv))
    }
}

x <- "hello"

f(x)
f("x")

rev_f(x)
rev_f("x")