📝 Check off the primitive-union rename

backlog.tasks

@@ -24,7 +24,7 @@ v1.0:
     ☐ Document all exported types and functions
     ☐ Add JSDoc for public APIs
 ☐ Test coverage meets threshold
-    ☐ Achieve 100% branch coverage on `src/primitive.ts`
+    ☐ Achieve 100% branch coverage on `src/primitive-union.ts`
     ☐ Achieve 100% branch coverage on `src/index.ts`
 
 Testing:
@@ -42,7 +42,7 @@ Testing:
 ☐ Type hole when using broad types like string as a universe @high
     ☐ handlers cannot be exhaustive, yet it is possible to not have a fallback
     ☐ one test even exploits this, I think for a negative test
-    ☐ does the same type hole exist for tagged-union matchers or primitive matchers only?
+    ☐ does the same type hole exist for tagged-union matchers or primitive-union matchers only?
 
 Matcher:
 ✔ Clean up: adopt the 3-overload matcher (`src/prototype-ac2.ts`) and delete the prototypes @high @done
@@ -55,10 +55,11 @@ Matcher:
 ✔ Implement matcher with similar API like matcher from primitive.ts @high @done
     → `getTaggedUnionMatcher` / `getTaggedUnionMatcherW`, curried on the discriminant key
     → fallback is the second argument; `_` removed
-☐ Rename `primitive` to `primitive-union` and `getMatcher` to `getPrimitiveMatcher` @medium
+✔ Rename `primitive` to `primitive-union` and `getMatcher` to `getPrimitiveMatcher` @medium @done
     → `src/primitive.ts` / `src/primitive.test.ts` → `primitive-union.*`
     → `getMatcherW` → `getPrimitiveMatcherW` for symmetry with the tagged-union pair
     → update `src/index.ts`, `development/library.md` and any README references
+    → shipped as `getPrimitiveUnionMatcher` / `getPrimitiveUnionMatcherW`; kept `Union` for symmetry with the tagged-union pair
 ☐ when using a union type as a property, the current behavior of tagged union matcher is
     to pass never to handler parameters
     → new matcher function needed or can be fixed in tagged union matcher
@@ -72,7 +73,7 @@ Enhancements:
     ✔ Are there other primitive types that should be supported in union patterns? (e.g. `bigint`, `symbol`) @medium @done
         → added boolean, null and undefined; rejected `symbol` (compile-time brand, nothing at runtime) and `bigint` (not a property key)
 ☐ Allow boolean, null and undefined discriminant values in tagged-union patterns @medium
-    → needs the primitive matcher's `PatternKey` / `PatternParam` projection; see development/library.md § Tagged-union matcher
+    → needs the primitive-union matcher's `PatternKey` / `PatternParam` projection; see development/library.md § Tagged-union matcher
 
 Documentation:
 ☐ Bring README.md back to its previous form — synopsis and examples restored, in the correct place