sub-vec: optimize no-op case.

* lib.c (sub_vec): If range covers entire vector, just
return it.

* txr.1: Clarify that the output of sub may share structure
with the input regardless of type, not only when the input
is a list. This should have been updated when the optimizatin
was done in sub-str.

1 files changed, 1 insertions, 2 deletions

diff --git a/txr.1 b/txr.1
index 15b49b84..dd5eb172 100644
--- a/txr.1
+++ b/txr.1
@@ -26860,8 +26860,7 @@ The description of the
 operator\(emin particular, the section
 on Range Indexing\(emexplains the semantics of the range specification.
 
-If the sequence is a list, the output sequence may share substructure
-with the input sequence.
+The output sequence may share structure with the input sequence.
 
 If
 .meta sequence