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Creating
Reading
Writing
Teardown
Fine-grained reactivity over a plain object, at the granularity of a path. A reader of one path wakes only when that path’s value changes, where a Signal holding an object wakes every reader on any change.
Paths use the @semantic-ui/utils grammar: dotted keys (user.name), positional indices (list[0]), and keyed array segments (todos[#a3f].done). Cells are keyed by the literal path string, so address an element consistently. A reader of todos[#a3f].done is not woken by a positional write to todos[0].done that hits the same element.
Creating
reactiveObject
reactiveObject(initialValue, options);Creates a reactive wrapper over a plain object. initialValue defaults to {}.
Parameters
| Name | Type | Description |
|---|---|---|
| initialValue | object | The backing object |
| options | object | Optional configuration |
Options
| Name | Type | Default | Description |
|---|---|---|---|
| safety | 'clone' | 'reference' | 'none' |
'reference' |
Value-protection preset. clone copies on read and on inbound set/replace, none re-fires on every set. See Signal Options |
| equality | function | deep equality | Decides whether a written value differs from the value already at a path |
| clone | function | structured clone | Copies values under safety: 'clone' |
Example
Reading
get
reactiveObject.get(path);Returns the value at path and subscribes the running reaction to that path alone, so a later write to a disjoint path will not re-fire it.
Parameters
| Name | Type | Description |
|---|---|---|
| path | string | The path to read |
Returns
The value at path, or undefined if absent.
peek
reactiveObject.peek();reactiveObject.peek(path);Untracked read that subscribes to nothing. With a path, the value there. Without one, the whole backing object.
Parameters
| Name | Type | Description |
|---|---|---|
| path | string | Optional path to read |
Returns
The value at path, or the whole backing object when no path is given.
hasDependents
reactiveObject.hasDependents();reactiveObject.hasDependents(path);Whether any live reaction subscribes to path, or to the whole object when no path is given.
Returns
true when a live subscriber exists.
Writing
set
reactiveObject.set(path, value);Writes value at path, waking readers of that path, of its ancestors, and of any descendant whose resolved value changed.
Parameters
| Name | Type | Description |
|---|---|---|
| path | string | The path to write |
| value | any | The value to set |
Returns
true when the write changed the value, false for an equality-gated no-op or a write the backing object drops.
remove
reactiveObject.remove(path);Removes path so the key leaves the object, reading back absent rather than undefined-valued. A no-op when the path is already absent.
Parameters
| Name | Type | Description |
|---|---|---|
| path | string | The path to remove |
Returns
true when the removal changed the object.
replace
reactiveObject.replace(nextObject);Swaps the whole backing object and reseeds every live reader against the new one, waking only the paths whose value changed, including deep readers under a wholesale-replaced subtree. The path for fresh data arriving in bulk.
Parameters
| Name | Type | Description |
|---|---|---|
| nextObject | object | The replacement backing object |
clear
reactiveObject.clear();Replaces the backing object with an empty one.
Teardown
prune
reactiveObject.prune();Sweeps cells nobody subscribes to. replace and subtree writes sweep as they go, so this is the explicit hook for an instance driven only by set and remove.
stop
reactiveObject.stop();Drops every cell. Live subscribers stop receiving wakes and future reads mint fresh cells.