backtick notation

Could someone explain the thinking behind the backtick notation in
r-devel?

I think I understand that it can be used to refer to variable names
which would otherwise not conform to R syntax; however, assign and
as.name already allow you to do this.  Is there more to it than that?

assign and as.name are fairly limited.  For example, if you have a list or
data frame whose name is syntactically invalid it is quite difficult to
access or modify its columns.


	-thomas

Thomas Lumley			Assoc. Professor, Biostatistics
tlumley@u.washington.edu	University of Washington, Seattle