name(string) as.name(x) is.name(x)
name takes the given character string
and returns a name (i.e. symbol) which has that string
as a printname.
as.name coerces its argument to be a name (i.e. symbol).
The argument must be of mode "character".
is.name returns true or false
depending on whether its arument is a name (symbol) or not.