sequence

Module nu.domains.shape.sequence.

Sequence family: an ordered collection in a shape fabric.

Forms weave the Python sequence surface with the shape collection ops, tier by tier, and type every result by what the slot declared: an element reads as the declared value's form, and a slice carries the declared element type on.

Refs add descent. ref[i] is the child ref at that position, built by the fabric from the declared value; a slice stays a value.

Name	Sort	Call	Meaning
MutableSequenceRef	`ref`	`MutableSequenceRef(address, parent_ref=None, owner_shape=None)`	Mutable ordered container Ref.
ReactiveSequenceRef	`ref`	`ReactiveSequenceRef(address, parent_ref=None, owner_shape=None)`	Reactive ordered container Ref.
SequenceRef	`ref`	`SequenceRef(address, parent_ref=None, owner_shape=None)`	Ordered container Ref; `ref[i]` navigates to the element's child Ref.

MutableSequenceRef

Mutable ordered container Ref.

MutableSequenceRef(address, parent_ref=None, owner_shape=None)

Path nu.domains.shape.MutableSequenceRef. Kind Ref, sort ref, cardinality scalar.

Adds: append(v), extend(), insert(i,v), pop(), ..., store(v), erase().

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, missing_ok=False)`	`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.sequence.SequenceRef:

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

From nu.domains.shape.sequence.SequenceForm:

Call	Builds	Meaning
`.iter()`	`Iterator`	A lazy stream over its elements, typed by the declared value.

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.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.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.collection.CollectionForm:

Call	Builds	Meaning
`.exists()`	`Bool`	Whether this collection slot holds a value, as a `Bool`.
`.missing()`	`Bool`	Whether this slot holds no value, as a `Bool`: the negation of `exists()`.

From nu.lang.forms.Form:

Call	Builds	Meaning
`a == b`	`Bool`	Self equal to other by value: an `Eq` term, never a Python bool.
`a != b`	`Bool`	Self not equal to other by value: a `Ne` term, never a Python bool.
`.is_empty()`	`Bool`	True if this Form yields the EMPTY sentinel.
`.not_empty()`	`Bool`	True if this Form does not yield EMPTY.
`.fallback(*alternatives)`	`Self`	The first of this value and `alternatives` that is not EMPTY.

Undocumented: example.

ReactiveSequenceRef

Reactive ordered container Ref.

ReactiveSequenceRef(address, parent_ref=None, owner_shape=None)

Path nu.domains.shape.ReactiveSequenceRef. Kind Ref, sort ref, cardinality scalar.

Adds: on_change(), on_child_change(), on_children_change(), on_descendants_change() on top of MutableSequenceRef.

Inherited methods

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

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

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, missing_ok=False)`	`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.sequence.SequenceRef:

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

From nu.domains.shape.sequence.SequenceForm:

Call	Builds	Meaning
`.iter()`	`Iterator`	A lazy stream over its elements, typed by the declared value.

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.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.collection.ReactiveCollectionForm:

Call	Builds	Meaning
`.on_child_change(address)`	`OnChildChange`	Observe writes at one child's own address; for its subtree use `on_descendants_change`.
`.on_children_change()`	`OnChildrenChange`	Observe writes at the direct children only; for subtrees use `on_descendants_change`.
`.on_descendants_change()`	`OnDescendantsChange`	Observe changes across descendants matching `pattern`.

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

Call	Builds	Meaning
`.exists()`	`Bool`	Whether this collection slot holds a value, as a `Bool`.
`.missing()`	`Bool`	Whether this slot holds no value, as a `Bool`: the negation of `exists()`.

From nu.lang.forms.Form:

Call	Builds	Meaning
`a == b`	`Bool`	Self equal to other by value: an `Eq` term, never a Python bool.
`a != b`	`Bool`	Self not equal to other by value: a `Ne` term, never a Python bool.
`.is_empty()`	`Bool`	True if this Form yields the EMPTY sentinel.
`.not_empty()`	`Bool`	True if this Form does not yield EMPTY.
`.fallback(*alternatives)`	`Self`	The first of this value and `alternatives` that is not EMPTY.

Undocumented: example.

SequenceRef

Ordered container Ref; ref[i] navigates to the element's child Ref.

SequenceRef(address, parent_ref=None, owner_shape=None)

Path nu.domains.shape.SequenceRef. Kind Ref, sort ref, cardinality scalar.

Navigation is defined once here and routes through _wrap_item_ref, the one hook that returns a ref rather than a form. It is a substrate plug-point on StructuredRef: the child is always a fabric's own ref, so the fabric's substrate base supplies it, and a fabric that leaves it out fails loudly.

Methods

`a[key]`

Int index navigates to the child Ref; slice routes to the form-level slice op.

Builds StructuredRef.

Arguments

Name	Type	Default	Meaning
`index`	`object`

Undocumented: example.

Inherited methods

From nu.domains.shape.sequence.SequenceForm:

Call	Builds	Meaning
`.iter()`	`Iterator`	A lazy stream over its elements, typed by the declared value.

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.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.collection.CollectionForm:

Call	Builds	Meaning
`.exists()`	`Bool`	Whether this collection slot holds a value, as a `Bool`.
`.missing()`	`Bool`	Whether this slot holds no value, as a `Bool`: the negation of `exists()`.

From nu.lang.forms.Form:

Call	Builds	Meaning
`a == b`	`Bool`	Self equal to other by value: an `Eq` term, never a Python bool.
`a != b`	`Bool`	Self not equal to other by value: a `Ne` term, never a Python bool.
`.is_empty()`	`Bool`	True if this Form yields the EMPTY sentinel.
`.not_empty()`	`Bool`	True if this Form does not yield EMPTY.
`.fallback(*alternatives)`	`Self`	The first of this value and `alternatives` that is not EMPTY.

Undocumented: example.

sequence

MutableSequenceRef

ReactiveSequenceRef

SequenceRef

a[key]

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`a[key]`