Module riakc_set

Encapsulates a set data-type.

Behaviours: riakc_datatype.

Description

Encapsulates a set data-type. Riak's sets differ from Erlang set types in several ways:

Only binaries are allowed as elements. Convert other terms to a binary before adding them.
Like the other eventually-consistent types, updates (add_element/2 and del_element/2) are not applied to local state. Instead, additions and removals are captured for later application by Riak.
Additions and removals are non-exclusive. You can add and remove the same element in the same session, both operations will be performed in Riak (removal first). Removals performed without a context may result in failure.
You may add an element that already exists in the original set value, and remove an element that does not appear in the original set value. This is non-intuitive, but acts as a safety feature: a client code path that requires an element to be present in the set (or removed) can ensure that intended state by applying an operation.
The query functions size/1, is_element/1 and fold/3 only operate on the original value of the set, disregarding local updates.

abstract datatype: riakc_set()

simple_set_op() = {add_all, [binary()]} | {remove_all, [binary()]}

add_element/2	Adds an element to the set.
add_elements/2	Adds elements to the set.
del_element/2	Removes an element from the set.
fold/3	Folds over the members of the set.
is_element/2	Test whether an element is a member of the set.
is_type/1	Determines whether the passed term is a set container.
new/0	Creates a new, empty set container type.
new/1	Creates a new set container with the opaque context.
new/2	Creates a new set container with the given members and opaque context.
size/1	Returns the cardinality (size) of the set.
to_op/1	Extracts an operation from the set that can be encoded into an update request.
type/0	Returns the symbolic name of this container.
value/1	Returns the original value of the set as an ordset.