Nothing
library("listenv")
ovars <- ls(envir = globalenv())
oopts <- options(warn = 1)
x <- listenv()
length(x) <- 3L
names(x) <- c("a", "b", "c")
stopifnot(length(x) == 3L)
print(mapping(x))
var <- get_variable(x, "a")
stopifnot(!is.na(var))
stopifnot(length(x) == 3L)
print(mapping(x))
var <- get_variable(x, "b")
stopifnot(!is.na(var))
stopifnot(length(x) == 3L)
print(mapping(x))
var <- get_variable(x, "c")
stopifnot(!is.na(var))
stopifnot(length(x) == 3L)
print(mapping(x))
var <- get_variable(x, "d")
stopifnot(!is.na(var))
stopifnot(length(x) == 4L)
print(mapping(x))
var <- get_variable(x, 4L)
stopifnot(!is.na(var))
stopifnot(length(x) == 4L)
print(mapping(x))
x$b <- 2
var <- get_variable(x, "b")
stopifnot(!is.na(var))
stopifnot(length(x) == 4L)
print(mapping(x))
var <- get_variable(x, length(x) + 1L)
stopifnot(length(x) == 5L)
print(names(x))
print(mapping(x))
## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
## Allocation
## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
x <- listenv()
length(x) <- 3L
print(x[[1]])
print(x[[2]])
print(x[[3]])
## Out-of-bound subsetting
res <- try(x[[0]], silent = TRUE)
stopifnot(inherits(res, "try-error"))
## Out-of-bound subsetting
res <- try(x[[4]], silent = TRUE)
stopifnot(inherits(res, "try-error"))
print(get_variable(x, 1L, mustExist = FALSE))
print(get_variable(x, 2L, mustExist = FALSE))
print(get_variable(x, 3L, mustExist = FALSE))
## Out-of-bound element
res <- try(var <- get_variable(x, 0L, mustExist = TRUE), silent = TRUE)
stopifnot(inherits(res, "try-error"))
## Out-of-bound element
res <- try(var <- get_variable(x, length(x) + 1L, mustExist = TRUE),
silent = TRUE)
stopifnot(inherits(res, "try-error"))
## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
## Exception handling
## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
x <- listenv()
length(x) <- 3L
names(x) <- c("a", "b", "c")
## Non-existing element
res <- try(var <- get_variable(x, "z", mustExist = TRUE), silent = TRUE)
stopifnot(inherits(res, "try-error"))
res <- try(var <- get_variable(x, c("a", "b")), silent = TRUE)
stopifnot(inherits(res, "try-error"))
res <- try(var <- get_variable(x, 1 + 2i), silent = TRUE)
stopifnot(inherits(res, "try-error"))
## Cleanup
options(oopts)
rm(list = setdiff(ls(envir = globalenv()), ovars), envir = globalenv())
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