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changelog/0.17.6.md

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+## [0.17.6](https://www.npmjs.com/package/@sinclair/typebox/v/0.17.6)
+
+Changes:
+
+- Added `Type.Rec(...)` function.
+
+Notes:
+
+This update introduces the `Type.Rec()` function for enabling Recursive Types. Please note that due to current inference limitations in TypeScript, TypeBox is unable to infer the type and resolves inner types to `any`. 
+
+This functionality enables for complex self referential schemas to be composed. The following creates a binary expression syntax node with the expression self referential for left and right operands.
+
+```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.