improve JSON Schema output (#585)

.changeset/shy-eggs-march.md

@@ -0,0 +1,12 @@
+---
+"@effect/schema": patch
+---
+
+improve JSON Schema output:
+
+- rename `dependencies` to `$defs`
+- remove `"type"` from const schemas
+- use `"oneOf"` for enums and add `"title"`s
+- add support for `record(pattern, number)`
+- add `"$id"` and `"$comment"` properties
+- literals should be converted to `enum` instead of `anyOf`, closes #579

docs/modules/JSONSchema.ts.md

@@ -12,13 +12,13 @@ Added in v1.0.0
 
 <h2 class="text-delta">Table of contents</h2>
 
-- [JSON Schema](#json-schema)
+- [encoding](#encoding)
   - [from](#from)
   - [to](#to)
 
 ---
 
-# JSON Schema
+# encoding
 
 ## from
 

src/AST.ts

@@ -311,6 +311,9 @@ export const createLiteral = (
  */
 export const isLiteral = (ast: AST): ast is Literal => ast._tag === "Literal"
 
+/** @internal */
+export const _null = createLiteral(null)
+
 /**
  * @category model
  * @since 1.0.0