collection

Module nu.domains.shape.forms.collection.

Shape-domain Collection Form chain.

Pure Form mixins: no Ref or substrate knowledge. They sit BETWEEN the generic collection forms and the concrete Refs, adding shape-domain ops (existence checks, fabric-level set/erase, tree-aware observation) on top of whatever generic collection surface the Ref already exposes.

on_change() (observe self) is deliberately absent here. It is generic and lives on the generic ReactiveXxxForm tiers in nu.forms.collections.abc, returning nu.core.reactive.OnChange. ReactiveCollectionForm provides only the three tree-aware methods, which reach for the shape-tier counterparts in nu.core.reactive too: one unified location for every reactive query.

Name	Call	Meaning
CollectionForm	`CollectionForm()`	Shape collection Form. Ops: `exists()`, `missing()`, `extract()`.
MutableCollectionForm	`MutableCollectionForm()`	Mutable shape collection Form. Adds `set(value)` and `erase()`.
ReactiveCollectionForm	`ReactiveCollectionForm()`	Reactive shape collection Form. Adds tree-aware observation.

CollectionForm

Shape collection Form. Ops: exists(), missing(), extract().

CollectionForm()

Path nu.domains.shape.forms.CollectionForm.

Methods

`.exists()`

Build an Exists query.

Builds Exists.

Undocumented: example.

`.missing()`

Build a Missing query.

Builds Missing.

Undocumented: example.

`.extract()`

Build an Extract query.

Builds Extract.

Undocumented: example.

Inherited methods

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.

From builtins.object:

Call	Builds	Meaning
`a < b`		Return self<value.
`a <= b`		Return self<=value.
`a == b`		Return self==value.
`a != b`		Return self!=value.
`a > b`		Return self>value.
`a >= b`		Return self>=value.

Undocumented: example.

MutableCollectionForm

Mutable shape collection Form. Adds set(value) and erase().

MutableCollectionForm()

Path nu.domains.shape.forms.MutableCollectionForm.

Methods

`.set(value)`

Build a SetCmd.

Builds SetCmd.

Arguments

Name	Type	Default	Meaning
`value`	`object`

Undocumented: example.

`.erase()`

Build an Erase.

Builds Erase.

Undocumented: example.

`.init(value)`

Set value iff the collection is currently missing.

Builds IfDo.

Arguments

Name	Type	Default	Meaning
`value`	`object`

Undocumented: example.

Inherited methods

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

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

From builtins.object:

Call	Builds	Meaning
`a < b`		Return self<value.
`a <= b`		Return self<=value.
`a == b`		Return self==value.
`a != b`		Return self!=value.
`a > b`		Return self>value.
`a >= b`		Return self>=value.

Undocumented: example.

ReactiveCollectionForm

Reactive shape collection Form. Adds tree-aware observation.

ReactiveCollectionForm()

Path nu.domains.shape.forms.ReactiveCollectionForm.

on_change() (observe self) is intentionally absent. It is generic and supplied by the generic ReactiveXxxForm tier via MRO.

Methods

`.on_child_change(address)`

Observe changes at a specific child address.

Builds OnChildChange.

Arguments

Name	Type	Default	Meaning
`address`	`object`

Undocumented: example.

`.on_children_change()`

Observe changes across all direct children.

Builds OnChildrenChange.

Undocumented: example.

`.on_descendants_change()`

Observe changes across descendants matching pattern.

Builds OnDescendantsChange.

Undocumented: example.

Inherited methods

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.
`.extract()`	`Extract`	Build an `Extract` 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.

From builtins.object:

Call	Builds	Meaning
`a < b`		Return self<value.
`a <= b`		Return self<=value.
`a == b`		Return self==value.
`a != b`		Return self!=value.
`a > b`		Return self>value.
`a >= b`		Return self>=value.

Undocumented: example.

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