1 files changed, 17 insertions, 7 deletions

diff --git a/u/trace/metrics.ts b/u/trace/metrics.ts
index a26ee5d..4ddde06 100644
--- a/u/trace/metrics.ts
+++ b/u/trace/metrics.ts
@@ -4,6 +4,7 @@ import {
   type ITraceWith,
   type Mapper,
   type SideEffect,
+  type Supplier,
 } from "@emprespresso/pengueno";
 
 export enum Unit {
@@ -16,10 +17,13 @@ export interface IMetric {
   readonly time: IEmittableMetric;
   readonly failure: IMetric;
   readonly success: IMetric;
-  readonly _isIMetric: true;
+  readonly warn: IMetric;
+  readonly children: Supplier<Array<IMetric>>;
+
+  readonly _tag: "IMetric";
 }
 export const isIMetric = (t: unknown): t is IMetric =>
-  isObject(t) && "_isIMetric" in t;
+  isObject(t) && "_tag" in t && t._tag === "IMetric";
 
 export interface IEmittableMetric {
   readonly name: string;
@@ -35,9 +39,9 @@ export class EmittableMetric implements IEmittableMetric {
     return {
       name: this.name,
       unit: this.unit,
-      _isMetricValue: true as true,
       emissionTimestamp: Date.now(),
       value,
+      _tag: "MetricValue",
     };
   }
 }
@@ -48,15 +52,21 @@ export class Metric implements IMetric {
     public readonly time: IEmittableMetric,
     public readonly failure: Metric,
     public readonly success: Metric,
-    public readonly _isIMetric: true = true,
+    public readonly warn: Metric,
+    public readonly _tag: "IMetric" = "IMetric",
   ) {}
 
+  public children() {
+    return [this.failure, this.success, this.warn];
+  }
+
   static fromName(name: string): Metric {
     return new Metric(
       new EmittableMetric(`${name}.count`, Unit.COUNT),
       new EmittableMetric(`${name}.elapsed`, Unit.MILLISECONDS),
       Metric.fromName(`${name}.failure`),
       Metric.fromName(`${name}.success`),
+      Metric.fromName(`${name}.warn`),
     );
   }
 }
@@ -66,10 +76,10 @@ export interface MetricValue {
   readonly unit: Unit;
   readonly value: number;
   readonly emissionTimestamp: number;
-  readonly _isMetricValue: true;
+  readonly _tag: "MetricValue";
 }
 export const isMetricValue = (t: unknown): t is MetricValue =>
-  isObject(t) && "_isMetricValue" in t;
+  isObject(t) && "_tag" in t && t._tag === "MetricValue";
 
 export const isMetricsTraceSupplier = (t: unknown): t is MetricsTraceSupplier =>
   isMetricValue(t) || isIMetric(t);
@@ -98,7 +108,7 @@ export class MetricsTrace implements ITrace<MetricsTraceSupplier> {
     const foundMetricValues = this.tracing.flatMap((
       [tracing, startedTracing],
     ) =>
-      [tracing, tracing.success, tracing.failure]
+      [tracing, ...tracing.children()]
         .filter((_tracing) => metric === _tracing)
         .flatMap((metric) => [
           this.addMetric(metric, startedTracing),