[Rd] Is this a bug in `[`?

[Rui Barradas]

Hello,

Maybe I am not understanding how negative indexing works but

1) This is right.

(1:10)[-1]
#[1]  2  3  4  5  6  7  8  9 10

2) Are these right? They are at least surprising to me.

(1:10)[-0]
#integer(0)

(1:10)[-seq_len(0)]
#integer(0)


It was the last example that made me ask, seq_len(0) whould avoid an 
if/else or something similar.


Thanks in advance,

Rui Barradas