up

TODO.md

@@ -2,7 +2,14 @@
 >
 > - https://github.com/cicada-lang/propagator/issues/2
 
+fix `maybeUnwrapSupported` -- learn from `nary-unpacking`
+
 `barometer` -- 的测试带上 `promises` -- 用论文中讲故事的方式来写测试
+
+fix `isContradiction` for `Supported`
+
+- `isContradiction` should be a generic
+
 test about "a justified-intervals anomaly"
 
 - 即 supports 的集合可能与 supported value put 进来的顺序有关

src/dependency/supportedMerge.ts

@@ -8,8 +8,14 @@ export function supportedMerge<A, B>(
 ): Supported<A | B> | Contradiction {
   const mergedContent = merge(content.content, increment.content)
 
+  // 这里的 cases 可以写成更对称的样子，
+  // 但是这里为了效率（少调用 merge 的次数），
+  // 写的不是那么对称了。
+
   if (mergedContent === content.content) {
+    // 正向和反向的 implies 代表等价。
     if (implies(increment, content)) {
+      // 倾向于 content，除非 increment 真的有更多信息。
       if (setIsSubsetOf(content.supports, increment.supports)) {
         return content
       } else {

src/examples/barometer.test.ts

@@ -1,6 +1,7 @@
 import assert from "node:assert"
 import { test } from "node:test"
 import { Cell, put } from "../cell/index.js"
+import { Supported } from "../dependency/index.js"
 import { Interval, intervalAlmostEqual } from "../interval/index.js"
 import { run } from "../scheduler/index.js"
 import { fallDuration, similarTriangles } from "./barometer.js"
@@ -72,3 +73,15 @@ test("examples / barometer / similarTriangles & fallDuration", async () => {
     ),
   )
 })
+
+test("examples / barometer / with supported value", async () => {
+  const [barometerShadow, barometerHeight, buildingShadow, buildingHeight] =
+    similarTriangles()
+  put(buildingShadow, Supported(Interval(54.9, 55.1), new Set(["shadows"])))
+  put(barometerHeight, Supported(Interval(0.3, 0.32), new Set(["shadows"])))
+  put(barometerShadow, Supported(Interval(0.36, 0.37), new Set(["shadows"])))
+
+  // await run()
+
+  // console.log(buildingHeight)
+})

src/generic/defineGeneric.ts

@@ -23,12 +23,15 @@ export function defineGeneric(
     if (options.default) {
       return options.default(...args)
     } else {
-      console.error({
-        who: "GenericDefinition",
-        constroctor: "defineGeneric",
-        definition,
-        args,
-      })
+      console.dir(
+        {
+          who: "GenericDefinition",
+          constroctor: "defineGeneric",
+          definition,
+          args,
+        },
+        { depth: null },
+      )
       throw new Error(`[GenericDefinition] Unhandled args and not default.`)
     }
   }

src/merge/merge.ts

@@ -33,7 +33,18 @@ import { theContradiction } from "./Contradiction.js"
 // treatment of their existing content versus incoming content. Having
 // merge return the wrong one could lead to spurious infinite loops.
 
-export const merge = defineGeneric() // no default, be explicit.
+export const merge = defineGeneric({
+  default(...args) {
+    // no default, be explicit.
+    console.error({
+      who: "merge",
+      message: "Unhandled args.",
+      args,
+    })
+
+    throw new Error(`[merge] Unhandled args.`)
+  },
+})
 
 // Second argument is redundant for `merge`.
 export function implies<A, B>(x: A, y: B): boolean {

src/propagator/definePrimitive.ts

@@ -1,4 +1,5 @@
 import { Cell, addPropagator, isNothing, nothing, put } from "../cell/index.js"
+import { isSupported } from "../dependency/index.js"
 import { schedule } from "../scheduler/index.js"
 import type { MaybePromise } from "../utils/MaybePromise.js"
 import { repeatApply } from "../utils/repeatApply.js"
@@ -86,6 +87,7 @@ function watch(cells: Array<Cell<any>>, propagator: Propagator): void {
 function lift(
   fn: (...args: Array<any>) => MaybePromise<any>,
 ): (...args: Array<Cell<any>>) => MaybePromise<any> {
+  fn = maybeUnwrapSupported(fn)
   fn = skipIncompleteInputs(fn)
 
   return (...inputs) => {
@@ -98,6 +100,15 @@ function lift(
   }
 }
 
+function maybeUnwrapSupported(
+  fn: (...args: Array<any>) => MaybePromise<any>,
+): (...args: Array<any>) => MaybePromise<any> {
+  return (...args) => {
+    args = args.map((arg) => (isSupported(arg) ? arg.content : arg))
+    return fn(...args)
+  }
+}
+
 // # 参数不全时的处理
 // 函数只能在参数齐全的情况下才能作用，
 // 因此代表函数的 propagator，