refs.list

Module nustd.mem.refs.list.

Dict sequence reference: ordered container backed by nested list.

Name	Sort	Call	Meaning
ListRef	`ref`	`ListRef(address, item_type, item_value_type, parent_ref=None, owner_shape=None)`	A sequence slot in the dict substrate, holding one plain list of values.

ListRef

A sequence slot in the dict substrate, holding one plain list of values.

ListRef(address, item_type, item_value_type, parent_ref=None, owner_shape=None)

Path nustd.mem.ListRef. Kind Ref, sort ref, cardinality scalar.

Subscripting with an int descends rather than reads: ref[i] is an ItemRef at that index inside the stored list, settable and erasable on its own. A slice instead routes to the sequence-level slice call and yields a new list.

Notes

The stored value is an ordinary list and a read hands back that live object, so a mutation through the ref is visible to anyone else holding it.
In-place calls read the container first and do nothing when the slot is absent, so set an empty list before the first append.
The declared element type is metadata; nothing coerces or rejects what is written.

Example

class Port(nu.Shape):
    tags = nustd.mem.ListRef.slot(str)
data = {"tags": ["a"]}
ctx = nu.Context().bind(dict, data, Port)
_ = nu.run(Port.tags.append("b"), ctx)
nu.run(Port.tags[1], ctx)[0]
data

'b'
{'tags': ['a', 'b']}

Inherited methods

From nu.forms.collections.abc.sequence.MutableSequenceForm:

Call	Builds	Meaning
`.append(value)`	`Any`	Append value to the end of self.
`.extend(other)`	`Any`	Extend self with the elements of other, in order.
`.insert(index, value)`	`Any`	Insert value at index, shifting later elements right.
`.pop(index=-1)`	`ElementResultT`	Remove and return the element at index.
`.del_at(index)`	`Any`	Remove the element at index.
`.remove(value)`	`Any`	Remove the first occurrence of value.
`.reverse()`	`Any`	Reverse self in place.
`.sort()`	`Any`	Sort self in place, ascending, using the elements' natural order.
`.copy()`	`CollectionResultT`	Shallow copy of self: a new sequence with the same elements.
`.clear()`	`Any`	Remove every element from self.

From nu.domains.shape.refs.sequence.SequenceRef:

Call	Builds	Meaning
`a[key]`	`ItemResultT`	Int index navigates to the child Ref; slice routes to the form-level slice op.

From nu.forms.collections.abc.sequence.SequenceForm:

Call	Builds	Meaning
`.first_elem()`	`ElementResultT`	First element of self.
`.last_elem()`	`ElementResultT`	Last element of self.
`.index(value)`	`Int`	Lowest index in self where value is found, searching from the left.
`.count(value)`	`Int`	Count of occurrences of value in self.
`.reversed()`	`CollectionResultT`	Self walked back to front, as a stream.

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.forms.collections.abc.sliceable.SliceableForm:

Call	Builds	Meaning
`.slice(start, stop, step=None)`	`ResultT`	Slice of self from start to stop, stepping by step.

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.

refs.list

ListRef

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