[Rd] Unexpected behavior of identical() with language objects

[Winston Chang]

I ran into this and found the result very surprising:

identical( quote({ a }),  quote({ a }) )
# FALSE

It seems related to curly braces. For example, parens work fine:
identical( quote(( a )),  quote(( a )) )
# TRUE

Is this expected behavior? I can't seem to find anything in the help
for identical that relates to this.

-Winston