Named Lists, Lists of Items, and Atomic Vectors
The classes "named.list" and "item.list" are merely some 'helper classes' for the construction of the classes "data.set" and "importer".
Class "named.list" extends the basic class "list" by an additional
slot "names". Its initialize method assures that the names
of the list are unique.
Class "item.list" extends the class "named.list", but does not
add any slots. From "named.list" it differs only by the
initialize method, which calls that for "named.list"
and makes sure that all elements of the list belong to
class "item".
Classes "atomic" and "double" are merely used for method selection.
new("named.list",a=1,b=2)
# This should generate an error, since the names
# are not unique.
try(new("named.list",a=1,a=2))
# Another error, one name is missing.
try(new("named.list",a=1,2))
# Also an error, the resulting list would be unnamed.
try(new("named.list",1,2))
new("item.list",a=1,b=2)
# Also an error: "item.list"s are "named.lists",
# and here the names would be non-unique.
try(new("item.list",a=1,a=2))Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.