From b6213f660b6a706f48289b492f305bc2f4620f80 Mon Sep 17 00:00:00 2001
From: Akshay Nair <phenax5@gmail.com>
Date: Thu, 10 Aug 2023 14:18:02 +0530
Subject: feat: style injection

---
 src/utils/adt.ts | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)
 create mode 100644 src/utils/adt.ts

(limited to 'src/utils/adt.ts')

diff --git a/src/utils/adt.ts b/src/utils/adt.ts
new file mode 100644
index 0000000..c19398b
--- /dev/null
+++ b/src/utils/adt.ts
@@ -0,0 +1,26 @@
+type TagValue<T, N> = T extends Tag<N, infer V> ? V : never
+
+export const match =
+  <R, T extends Tag<string, any>>(pattern: {
+    [key in T['tag'] | '_']?: (v: TagValue<T, key>) => R
+  }) =>
+  (tag: T): R =>
+    ((pattern as any)[tag.tag] || (pattern._ as any))(tag.value)
+
+type Tag<N, V> = { tag: N; value: V }
+export type Enum<T> = { [N in keyof T]: Tag<N, T[N]> }[keyof T]
+
+export const constructors = <T extends Tag<string, any>>(): {
+  [N in T['tag']]: TagValue<T, N> extends null | never
+    ? (value?: null | never) => T
+    : (value: TagValue<T, N>) => T
+} =>
+  new Proxy(
+    {},
+    {
+      get(_, k) {
+        return (value: any) => ({ tag: k, value })
+      },
+    },
+  ) as any
+
-- 
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