bypass

{bypass} provides a way to use the default behavior of internal generics, bypassing the S3 methods. This makes working with objects at the low level much easier and safer.

We provide counterparts to existing functions:

{base}	{bypass}
c	.c
dim	.dim
dim<-	.dim<-
$	.dollar
$<-	.dollar<-
lapply	.lapply
length	.length
lengths	.lengths
names	.names
names<-	.names<-
sapply	.sapply
[<-	.subset<-
[[<-	.subset2<-
unlist	.unlist

Note that base R already has .subset() and .subset2() as low level counterparts to [ and [[. check also {rlang} for low level versions of is.symbol(), is.na() etc

Additionally the functions with_bypass() and local_bypass() allow you to locally type the base versions and get the bypass behavior. This is especially useful for [<- and [[<-.

Installation

You can install the development version of bypass like so:

pak::pak("cynkra/bypass")

Example 1

library(bypass)
#> 
#> Attaching package: 'bypass'
#> The following object is masked from '.Rprofile':
#> 
#>     .c
## from ?bibentry
rref <- bibentry(
   bibtype = "Manual",
   title = "R: A Language and Environment for Statistical Computing",
   author = person("R Core Team"),
   organization = "R Foundation for Statistical Computing",
   address = "Vienna, Austria",
   year = 2014,
   url = "https://www.R-project.org/"
   )

# The S3 method makes the object hard to manipulate
identical(rref[[1]][[1]], rref)
#> [1] TRUE

# Base R helps here
.subset2(rref, c(1, 1))
#> [1] "R: A Language and Environment for Statistical Computing"

# though it looks bad when we want to combine indices types
.subset2(rref, 1) |> .subset2("title")
#> [1] "R: A Language and Environment for Statistical Computing"

# with {bypass} we can use the standard syntax
with_bypass(rref[[1]][["title"]])
#> [1] "R: A Language and Environment for Statistical Computing"

# `local_bypass()` is meant to be used in functions and is probably what
# you'll want to use
fun <- function(x) {
  local_bypass()
  x[[1]]$title <- "!!!!!!!!!!!!!!!!"
  x
}
fun(rref)
#> R Core Team (2014). _!!!!!!!!!!!!!!!!_. R Foundation for Statistical
#> Computing, Vienna, Austria. <https://www.R-project.org/>.

Example 2

x <- structure(list(a = 1, b = 2), class = "foo")
c.foo <- function(...) 42
dim.foo <- function(...) 42
`$.foo` <- function(...) 42
lapply.foo <- function(...) 42
length.foo <- function(...) 42
lengths.foo <- function(...) 42
names.foo <- function(...) 42
sapply.foo <- function(...) 42
`[.foo` <- function(...) 42
`[[.foo` <- function(...) 42
unlist.foo <- function(...) 42
  
c(x)
#> [1] 42
.c(x)
#> $a
#> [1] 1
#> 
#> $b
#> [1] 2

dim(x)
#> [1] 42
.dim(x)
#> NULL

x$a
#> [1] 42
.dollar(x, a)
#> [1] 1

lapply(x, identity)
#> $a
#> [1] 42
#> 
#> $b
#> [1] 42
.lapply(x, identity)
#> $a
#> [1] 1
#> 
#> $b
#> [1] 2

sapply(x, identity)
#>  a  b 
#> 42 42
.sapply(x, identity)
#> a b 
#> 1 2

length(x)
#> [1] 42
.length(x)
#> [1] 2

names(x)
#> [1] 42
.names(x)
#> [1] "a" "b"

unlist(x)
#> [1] 42
.unlist(x)
#> a b 
#> 1 2

# NOTE: `local_bypass()` should normally be called in a function so we don't 
# change the global state, here for demo purposes:
local_bypass()
c(x)
#> $a
#> [1] 1
#> 
#> $b
#> [1] 2
dim(x)
#> NULL
x$a
#> [1] 1
lapply(x, identity)
#> $a
#> [1] 1
#> 
#> $b
#> [1] 2
sapply(x, identity)
#> a b 
#> 1 2
length(x)
#> [1] 2
names(x)
#> [1] "a" "b"
unlist(x)
#> a b 
#> 1 2