An immutable signal derived from a previous pulse through a transformation step — a causal link in the signal's journey.
An EvolvedPulse is what you get when you call evolve on any pulse. It carries a reference to its parent, preserving the signal's lineage without duplicating data. This is how the framework builds causal chains while keeping memory usage low.
When to use
- Causal Traceability: You never implement this interface. It's returned by evolve. Use it when you need to trace a signal's transformation history — for debugging, auditing, or explainability.
- Tracing a signal's journey through the reactive graph.
- Debugging or auditing the evolution of a pulse.
- Building causal chains for explainability (XAI).
- Preserving provenance across transformation steps.
- Understanding which transformations were applied to a signal.
How it works
- Each evolved pulse links back to its parent — the pulse it came from.
- The trace property accumulates steps from all ancestors.
- The root always points to the original pulse that started the chain.
- The payload is inherited from the root — evolved pulses don't duplicate it.
Non‑obvious: evolution is not mutation
EvolvedPulse is immutable. When you call evolve, you get a new pulse that points to the old one. The old pulse is still there — unchanged, available for reference — which is why you can trace the entire lineage without copying data.
Example
final root = Pulse<int>(42);
final evolved = root.evolve(step: 'validation');
print(evolved is EvolvedPulse); // true
print(evolved.parent); // root
print(evolved.trace); // ['validation']
See also:
- Pulse.evolve – the method that creates evolved pulses.
- Pulse.withStep – a convenience wrapper around evolve.
- CollectivePulse – the flat bundle created by
+or Pulse.batch.
- Implemented types
-
- Pulse<
P>
- Pulse<
- Available extensions
Properties
- context → PulseContext
-
The operational tier and security authority under which this pulse propagates.
no setterinherited
- first → Pulse
-
The first element.
no setterinherited
- hashCode → int
-
The hash code for this object.
no setterinherited
- isComposite → bool
-
Indicates whether this pulse is a multi-message bundle (a collection).
no setterinherited
- isEmpty → bool
-
Whether this collection has no elements.
no setterinherited
- isGoverned → bool
-
Indicates whether this pulse is subject to explicit governance.
no setterinherited
- isInvalidated → bool
-
Indicates whether this message has reached its terminal lifecycle state.
no setterinherited
- isNotEmpty → bool
-
Whether this collection has at least one element.
no setterinherited
-
iterator
→ Iterator<
Pulse> -
Returns an iterator over the sub‑pulses in this pulse.
no setterinherited
- last → Pulse
-
The last element.
no setterinherited
- length → int
-
The number of elements in this Iterable.
no setterinherited
- parent → Pulse
-
The immediate causal ancestor of this pulse in the processing chain.
no setter
- payload → P?
-
The terminal data result of the evolution chain.
no setteroverride
- policy → PulseEphemeralPolicy?
-
The lifecycle governance policy for this pulse.
no setterinherited
- priority → int
-
The execution priority of this pulse (0‑100, higher = more urgent).
no setterinherited
-
root
→ Pulse<
P> -
The primordial ancestor that initiated this pulse's causal lineage.
no setterinherited
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
-
shell
→ PulseShell<
P, Receptor< Cell> > -
Returns a Defensive Proxy of this pulse for untrusted receivers.
no setterinherited
- single → Pulse
-
Checks that this iterable has only one element, and returns that element.
no setterinherited
- source → Cell?
-
The cell that originally emitted this pulse's lineage.
no setterinherited
- timestamp → DateTime
-
The exact moment this pulse was synthesised.
no setterinherited
-
trace
→ List<
String> -
An ordered sequence of steps documenting the signal's journey.
no setterinherited
- type → String?
-
A semantic identifier representing the category or intent of the pulse.
no setterinherited
-
unmodifiable
→ Pulse<
P> -
Returns a read‑only projection of this pulse, ensuring structural and
payload-level finality for the current propagation hop.
no setterinherited
Methods
-
any(
bool test(Pulse element)) → bool -
Checks whether any element of this iterable satisfies
test.inherited -
attach(
dynamic context) → Pulse< P> -
Available on Pulse<
Returns a new version of this pulse with updatedP> , provided by the PulseExtension extensioncontextmetadata. -
attach(
dynamic context) → Iterable< Pulse> -
Available on Iterable<
Returns a new collection of pulses, each with the providedPulse> , provided by the PulseIterableExtension extensioncontextmetadata attached. -
batch(
) → Pulse -
Available on Iterable<
Aggregates multiple signals into a single, flat CollectivePulse.Pulse> , provided by the PulseIterableExtension extension -
cast<
R> () → Iterable< R> -
A view of this iterable as an iterable of
Rinstances.inherited -
cast<
T> () → Pulse< T> -
Available on Pulse<
Re-casts the pulse payload to typeP> , provided by the PulseExtension extensionTwhile maintaining causal history. -
compareTo(
Pulse other) → int -
Compares this pulse with another to determine relative execution precedence.
inherited
-
contains(
Object? element) → bool -
Whether the collection contains an element equal to
element.inherited -
elementAt(
int index) → Pulse -
Returns the
indexth element.inherited -
every(
bool test(Pulse element)) → bool -
Checks whether every element of this iterable satisfies
test.inherited -
evolve(
{Pulse? pulse, String? step, covariant PulseContext? context}) → Pulse -
Creates a derived version of this pulse for the next processing stage.
inherited
-
expand<
T> (Iterable< T> toElements(Pulse element)) → Iterable<T> -
Expands each element of this Iterable into zero or more elements.
inherited
-
firstWhere(
bool test(Pulse element), {Pulse orElse()?}) → Pulse -
The first element that satisfies the given predicate
test.inherited -
flatten(
) → Iterable< Pulse> -
Available on Iterable<
Recursively flattens any nested CollectivePulse structures into a sequence of simple pulses.Pulse> , provided by the PulseIterableExtension extension -
fold<
T> (T initialValue, T combine(T previousValue, Pulse element)) → T -
Reduces a collection to a single value by iteratively combining each
element of the collection with an existing value
inherited
-
followedBy(
Iterable< Pulse> other) → Iterable<Pulse> -
Creates the lazy concatenation of this iterable and
other.inherited -
forEach(
void action(Pulse element)) → void -
Invokes
actionon each element of this iterable in iteration order.inherited -
join(
[String separator = ""]) → String -
Converts each element to a String and concatenates the strings.
inherited
-
lastWhere(
bool test(Pulse element), {Pulse orElse()?}) → Pulse -
The last element that satisfies the given predicate
test.inherited -
lineage<
T> (LineageArgument arg) → List< T> -
Traverses the causal chain from the root ancestor to this pulse to
reconstruct a historical timeline of values.
inherited
-
map<
T> (T toElement(Pulse e)) → Iterable< T> -
The current elements of this iterable modified by
toElement.inherited -
map<
T> (T mapper(P payload)) → Pulse< T> -
Available on Pulse<
Transforms the payload of this pulse into a new typeP> , provided by the PulseExtension extensionTwhile preserving its causal history. -
mapEach<
T> (T mapper(dynamic payload)) → Iterable< Pulse< T> > -
Available on Iterable<
Transforms the payload of every pulse in the collection while preserving their individual causal traces.Pulse> , provided by the PulseIterableExtension extension -
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
reduce(
Pulse combine(Pulse value, Pulse element)) → Pulse -
Reduces a collection to a single value by iteratively combining elements
of the collection using the provided function.
inherited
-
scrutinize(
covariant Receptor< Cell> receptor, List? positionalArguments, [Map<Symbol, dynamic> ? namedArguments]) → dynamic -
Challenges a receptor to prove it has the authority to see this pulse.
inherited
-
singleWhere(
bool test(Pulse element), {Pulse orElse()?}) → Pulse -
The single element that satisfies
test.inherited -
skip(
int count) → Iterable< Pulse> -
Creates an Iterable that provides all but the first
countelements.inherited -
skipWhile(
bool test(Pulse element)) → Iterable< Pulse> -
Creates an
Iterablethat skips leading elements whiletestis satisfied.inherited -
take(
int count) → Iterable< Pulse> -
Creates a lazy iterable of the
countfirst elements of this iterable.inherited -
takeWhile(
bool test(Pulse element)) → Iterable< Pulse> -
Creates a lazy iterable of the leading elements satisfying
test.inherited -
tap(
void action(P payload)) → Pulse< P> -
Available on Pulse<
Executes a side-effectP> , provided by the PulseExtension extensionactionusing the current payload and returns this pulse instance. -
toList(
{bool growable = true}) → List< Pulse> -
Creates a List containing the elements of this Iterable.
inherited
-
toSet(
) → Set< Pulse> -
Creates a Set containing the same elements as this iterable.
inherited
-
toString(
) → String -
A string representation of this object.
inherited
-
where(
bool test(Pulse element)) → Iterable< Pulse> -
Creates a new lazy Iterable with all elements that satisfy the
predicate
test.inherited -
whereType<
T> () → Iterable< R> -
Creates a new lazy Iterable with all elements that have type
T.inherited -
withStep(
String step) → Iterable< Pulse> -
Available on Iterable<
Appends a diagnostic stage to the causal trace of every pulse in this collection.Pulse> , provided by the PulseIterableExtension extension -
withStep(
String step) → Pulse< P> -
Appends a diagnostic stage to the pulse's causal trace without branching
the causal chain.
inherited
Operators
-
operator +(
covariant Pulse other) → Pulse -
Combines this pulse and
otherinto a composite CollectivePulse.inherited -
operator ==(
Object other) → bool -
The equality operator.
inherited