jwutil (version 1.1.1)

set_attr_in_place: Set attribute on any SEXP in place

Description

Set attribute on any SEXP in place

Usage

set_attr_in_place(x, name, value)

Arguments

x

Any R object for which an attribute can be set

name

The name of the attribute, as length one character vector

value

Value to be assigned to that attribute

Examples

# NOT RUN {
# benchmark to see whether setting an attribute on a function argument and returning it does a copy.
f <- function(x) { attr(x, "a") <- FALSE; x }
p <- generate_random_short_icd9(1)
q <- generate_random_short_icd9(1e6)
times <- 1e5
microbenchmark::microbenchmark(f(p), set_attr_in_place(p, "a", FALSE),
                               f(q), set_attr_in_place(q, "a", FALSE), times = times)
p2 <- p3 <- generate_random_short_icd9(1)
set_attr_in_place(p2, "a", FALSE)
stopifnot(identical(f(p3), p2))
# oh dear, \code{f} does copy.

# see if we can return without deep copy using Rcpp:

p4 <- p
q4 <- q
setDecimalCodeInPlace(p4)
stopifnot(identical(p4, setDecimalCode(p4)))
microbenchmark::microbenchmark(setDecimalCodeInPlace(p), setDecimalCode(p), times = times)
microbenchmark::microbenchmark(setDecimalCodeInPlace(q), setDecimalCode(q), times = times)


# }