refs.set

Module nustd.kv.refs.set.

Virtuals set reference: unordered unique-element container backed by a View.

Name	Sort	Call	Meaning
SetRef	`ref`	`SetRef(address, item_type, view_type, parent_ref=None, owner_shape=None)`	A set slot in KV storage: unordered, unique elements, stored decomposed.

SetRef

A set slot in KV storage: unordered, unique elements, stored decomposed.

SetRef(address, item_type, view_type, parent_ref=None, owner_shape=None)

Path nustd.kv.SetRef. Kind Ref, sort ref, cardinality scalar.

Notes

Ops run against the live View, so membership and size are answered by storage rather than by reading the set out.
Elements have no addresses of their own to descend into: a set has no keys, so there is no element ref and no subscript.
The set algebra (union, intersection, ...) yields values; the in-place variants (update, difference_update, ...) are the ones that write.
Change observation covers the child, the children and the whole subtree, each with its own hook.
PrimitiveSetRef is the other choice: one opaque blob written whole.

Example

class Portfolio(Shape):
    members = SetRef.slot(str)
run(Portfolio.members.add("gor"), ctx)
run(Portfolio.members.contains("gor"), ctx)

Inherited methods

From nu.forms.collections.abc.set_.ReactiveSetForm:

Call	Builds	Meaning
`.on_change()`	`object`	Subscribe to any change on this set slot.

From nu.forms.collections.abc.set_.MutableSetForm:

Call	Builds	Meaning
`.add(value)`	`Any`	Add value to self.
`.remove(value)`	`Any`	Remove value from self.
`.discard(value)`	`Any`	Remove value from self if present.
`.pop()`	`ElementResultT`	Remove and return an arbitrary element from self.
`.clear()`	`Any`	Remove every element from self.
`.update(other)`	`Any`	Add every element of other to self.
`.intersection_update(other)`	`Any`	Keep only the elements of self also found in other.
`.difference_update(other)`	`Any`	Remove every element of other from self.
`.symmetric_difference_update(other)`	`Any`	Keep the elements in exactly one of self and other.

From nu.forms.collections.abc.set_.SetLikeForm:

Call	Builds	Meaning
`.union(other)`	`CollectionResultT`	Union of self and other.
`.intersection(other)`	`CollectionResultT`	Intersection of self and other.
`.difference(other)`	`CollectionResultT`	Elements of self that are not in other.
`.symmetric_difference(other)`	`CollectionResultT`	Elements in exactly one of self and other, not both.
`.issubset(other)`	`Bool`	Whether every element of self is in other.
`.issuperset(other)`	`Bool`	Whether every element of other is in self.
`.isdisjoint(other)`	`Bool`	Whether self and other share no elements.
`.copy()`	`CollectionResultT`	Shallow copy of self.
`a \| b`	`CollectionResultT`	Union: self \| other.
`a & b`	`CollectionResultT`	Intersection: self & other.
`a - b`	`CollectionResultT`	Difference: self - other.
`a ^ b`	`CollectionResultT`	Symmetric difference: self ^ other.

From nu.forms.collections.abc.collection.CollectionForm:

Call	Builds	Meaning
`.extract()`	`object`	Materialise the full subtree rooted at self.

From nu.forms.collections.abc.sized.SizedForm:

Call	Builds	Meaning
`.len()`	`Int`	Length of self.

From nu.forms.collections.abc.iterable.IterableForm:

Call	Builds	Meaning
`iter(a)`	`Iterator[ElementT]`	Open self into a lazy iterator stream (Python's `iter`).

From nu.forms.collections.abc.container.ContainerForm:

Call	Builds	Meaning
`.contains(item)`	`Bool`	Whether item is a member of self.

From nu.domains.shape.forms.collection.ReactiveCollectionForm:

Call	Builds	Meaning
`.on_child_change(address)`	`OnChildChange`	Observe changes at a specific child address.
`.on_children_change()`	`OnChildrenChange`	Observe changes across all direct children.
`.on_descendants_change()`	`OnDescendantsChange`	Observe changes across descendants matching `pattern`.

From nu.domains.shape.forms.collection.MutableCollectionForm:

Call	Builds	Meaning
`.set(value)`	`SetCmd`	Build a `SetCmd`.
`.erase()`	`Erase`	Build an `Erase`.
`.init(value)`	`IfDo`	Set `value` iff the collection is currently missing.

From nu.domains.shape.forms.collection.CollectionForm:

Call	Builds	Meaning
`.exists()`	`Exists`	Build an `Exists` query.
`.missing()`	`Missing`	Build a `Missing` query.

From nu.lang.forms.Form:

Call	Builds	Meaning
`.is_empty()`	`Bool`	True if this Form yields the EMPTY sentinel.
`.is_invalid()`	`Bool`	True if this Form yields the INVALID sentinel.
`.is_sentinel()`	`Bool`	True if this Form yields either sentinel (EMPTY or INVALID).
`.not_empty()`	`Bool`	True if this Form does not yield EMPTY.
`.not_invalid()`	`Bool`	True if this Form does not yield INVALID.