The is functions tests if an object (or an object in its attribute)
inherits particular class and returns TRUE if it does, otherwise FALSE.
is_edibble_design checks if it inherits edbl_design.
is_edibble_graph checks if it inherits edbl_graph.
is_edibble_table checks if it inherits edbl_table
is_edibble checks if the object inherits edbl.
The search is quite simple, it checks if
the object is edbl_design, failing that it looks to see if the
attribute "design" of the object is edbl_design.
is_named_design check if it inherits NamedDesign.
The get functions extracts the requested edibble component (table, graph,
or design) from the object if possible.
edbl_design tries to get edbl_design.
edbl_table tries to get edbl_table with no design attribute.
edbl_graph tries to get edbl_graph.
is_edibble_design(x)is_named_design(x)
is_edibble_table(x)
is_edibble_graph(x)
is_edibble(x)
is_edibble_levels(x)
is_nest_levels(x)
is_cross_levels(x)
edbl_design(x)
edbl_table(x)
A logical value.
An object.