Consider the following code snippets:
> list(quote(1 + 1), I(quote(1 + 1)))
[[1]]
1 + 1
[[2]]
[1] 2 # should also be 1 + 1!?
> str(list(quote(1 + 1), I(quote(1 + 1))))
List of 2
$ : language 1 + 1
$ : language + 1 1 # why is this line different from the one above?
..- attr(*, "class")= chr "AsIs"
> quote(1 + 1)
1 + 1
> I(quote(1 + 1))
1 + 1 # OK
> str(quote(1 + 1))
language 1 + 1
> str(I(quote(1 + 1)))
language + 1 1 # again different
- attr(*, "class")= chr "AsIs"
This inconsistency is particularly striking when printing the individual
elements of a list works but printing the whole list does not:
> l <- list(quote(length(a)), I(quote(length(a))))
> l[[1]]
length(a)
> l[[2]]
length(a)
> l
[[1]]
length(a)
[[2]]
Error in print(length(a)) : object 'a' not found
Should we consider this a bug? If so, I can add it to Bugzilla.
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