Subsetting vector (including lists) returns the same number of elements
as the subsetting vector, including unmatched elements which are
reported as `NA` or `NULL` (in case of lists).
Consider:
```
menu = list(
"bacon" = "foo",
"eggs" = "bar",
"beans" = "baz"
)
select = c("bacon", "eggs", "spam")
menu[select]
# $bacon
# [1] "foo"
#
# $eggs
# [1] "bar"
#
# $<NA>
# NULL
```
Wouldn't it be more logical to return named vector/list including names
of unmatched elements when subsetting using names? After all, the
unmatched elements are already returned. I.e., the output would look
like this:
```
menu[select]
# $bacon
# [1] "foo"
#
# $eggs
# [1] "bar"
#
# $spam
# NULL
```
The simple fix `menu[select] |> setNames(select)` solves, but it feels
to me like something that could be a default behaviour.
On slightly unrelated note, when I was asking if there is a better
solution, the `menu[select]` seems to allocate more memory than
`menu_env = list2env(menu); mget(select, envir = menu, ifnotfound =
list(NULL)`. Or the sapply solution. Is this a benchmarking artifact?
https://stackoverflow.com/q/77828678/4868692
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