Adding changelog.md

changelog.md

@@ -0,0 +1,98 @@
+
+
+## [0.17.6](https://www.npmjs.com/package/@sinclair/typebox/v/0.17.6)
+
+- Added `Type.Rec(...)` function.
+
+This update introduces the `Type.Rec()` function for enabling Recursive Types. This feature is enabled without support for static inference of the recursive type. This is due to current inference limitations around TypeScript recursive types. The `Self` argument passed on `Type.Rec(Self => ...)` is a `TAny` and will statically resolve to type `any`. Callers can optionally type assert if nessasary.
+
+```typescript
+const Operator = Type.Union([
+    Type.Literal('+'),
+    Type.Literal('-'),
+    Type.Literal('/'),
+    Type.Literal('*')
+])
+
+type Expression = Static<typeof Expression>
+
+// Defines a self referencing type.
+const Expression = Type.Rec(Self => Type.Object({
+    left:     Type.Union([Self, Type.Number()]), 
+    right:    Type.Union([Self, Type.Number()]),
+    operator: Operator
+}))
+
+function evaluate(expression: Expression): number {
+    const left = typeof expression.left  !== 'number' 
+        ? evaluate(expression.left as Expression)  // assert as Expression
+        : expression.left
+    const right = typeof expression.right  !== 'number' 
+        ? evaluate(expression.right as Expression) // assert as Expression
+        : expression.right
+    switch(expression.operator) {
+        case '+': return left + right
+        case '-': return left - right
+        case '*': return left * right
+        case '/': return left / right
+    }
+}
+
+const result = evaluate({
+    left: {
+        left: 10, 
+        operator: '*',
+        right: 4, 
+    },
+    operator: '+',
+    right: 2,
+}) // -> 42
+```
+
+This functionality is flagged as `EXPERIMENTAL` and awaits community feedback.
+
+## [0.17.4](https://www.npmjs.com/package/@sinclair/typebox/v/0.17.4)
+
+- Added `Type.Box()` and `Type.Ref()` functions.
+
+This update provides the `Type.Box()` function to enable common related schemas to grouped under a common namespace; typically expressed as a `URI`. This functionality is primarily geared towards allowing one to define a common set of domain objects that may be shared across application domains running over a network. The `Type.Box()` is intended to be an analog to `XML` `xmlns` namespacing.
+
+The `Type.Ref()` function is limited to referencing from boxes only. The following is an example.
+
+```typescript
+// Domain objects for the fruit service.
+const Fruit = Type.Box('https://fruit.domain.com', {
+    Apple:  Type.Object({ ... }),
+    Orange: Type.Object({ ... }),
+})
+
+// An order referencing types of the fruit service.
+const Order = Type.Object({
+    id:       Type.String(),
+    quantity: Type.Number(),
+    item:     Type.Union([
+        Type.Ref(Fruit, 'Apple'),
+        Type.Ref(Fruit, 'Orange')
+    ])
+})
+```
+
+Currently, `Type.Omit()`, `Type.Pick()`, `Type.Partial()`, `Type.Readonly()` and `Type.Intersect()` do not work with Reference Types. This may change in later revisions.
+
+This functionality is flagged as `EXPERIMENTAL` and awaits community feedback.
+
+## [0.17.1](https://www.npmjs.com/package/@sinclair/typebox/v/0.17.1)
+
+- Remove default `additionalProperties: false` constraint from all object schemas.
+
+This update removes the `additionalProperties: false` constraint on all object schemas. This constraint was introduced on `0.16.x` but has resulted in significant downstream problems composing schemas whose types `intersect`. This is due to a JSON schema design principle where constraints should only be added (never removed), and that intersection types may require removal of the `additionalProperties` constraint in some cases, this had resulted in some ambiguity with respect to how TypeBox should handle such intersections. 
+
+This update can also be seen as a precursor towards TypeBox potentially leveraging `unevaluatedProperties` for type intersection in future releases. Implementors should take note that in order to constrain the schema to known properties, one should apply the `additionalProperties: false` as the second argument to `Type.Object({...})`. 
+
+```typescript
+const T = Type.Object({
+    a: Type.String(),
+    b: Type.Number()
+}, { 
+    additionalProperties: false 
+})

example/index.ts

@@ -1,14 +1,10 @@
 import { Type, Static } from '@sinclair/typebox'
 
-type Node = Static<typeof Node>
+const Box = Type.Box('foo', {
+    Foo: Type.String()
+})
 
-const Node = Type.Rec(Self => Type.Object({
-    id:    Type.String(),
-    nodes: Type.Array(Self)
-}))
+const Foo = Type.Ref(Box, 'Foo')
+
+type Foo = Static<typeof Foo>
 
-function walk(node: Node) {
-    for(const inner of node.nodes) {
-        walk(inner as Node)
-    }
-}