From 74519010b30719c4ee4183ebd70d7381301182b1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Julien=20Valverd=C3=A9?= <julien.valverde@mailo.com>
Date: Wed, 20 May 2026 22:14:04 +0200
Subject: [PATCH] Refactor

---
 packages/effect-lens/src/Lens.ts | 31 ++++++++++++-------------------
 1 file changed, 12 insertions(+), 19 deletions(-)

diff --git a/packages/effect-lens/src/Lens.ts b/packages/effect-lens/src/Lens.ts
index a891549..77b7b54 100644
--- a/packages/effect-lens/src/Lens.ts
+++ b/packages/effect-lens/src/Lens.ts
@@ -35,16 +35,18 @@ extends Lens<A, ER, EW, RR, RW> {
     readonly [LensWithInternalsTypeId]: LensWithInternalsTypeId
 
     readonly update: (a: A) => Effect.Effect<void, EW, RW>
-    readonly withLock: <A1, E1, R1>(self: Effect.Effect<A1, E1, R1>) => Effect.Effect<A1, E1, R1>
+    readonly withLock: <A1, E1, R1>(self: Effect.Effect<A1, E1, R1>) => Effect.Effect<A1, EW | E1, RW | R1>
 }
 
 export const isLensWithInternals = (u: unknown): u is LensWithInternals<unknown, unknown, unknown, unknown, unknown> => Predicate.hasProperty(u, LensWithInternalsTypeId)
 
 export const asLensWithInternals = <A, ER, EW, RR, RW>(
     lens: Lens<A, ER, EW, RR, RW>
-): Effect.Effect<LensWithInternals<A, ER, EW, RR, RW>, never, never> => isLensWithInternals(lens)
-    ? Effect.succeed(lens as LensWithInternals<A, ER, EW, RR, RW>)
-    : Effect.die("Not a 'LensWithInternals'.")
+): LensWithInternals<A, ER, EW, RR, RW> => {
+    if (!isLensWithInternals(lens))
+        throw new Error("Not a 'LensWithInternals'.")
+    return lens as LensWithInternals<A, ER, EW, RR, RW>
+}
 
 
 export declare namespace LensImpl {
@@ -52,7 +54,7 @@ export declare namespace LensImpl {
         readonly get: Effect.Effect<A, ER, RR>,
         readonly changes: Stream.Stream<A, ER, RR>,
         readonly update: (a: A) => Effect.Effect<void, EW, RW>,
-        readonly withLock: <A1, E1, R1>(self: Effect.Effect<A1, E1, R1>) => Effect.Effect<A1, E1, R1>,
+        readonly withLock: <A1, E1, R1>(self: Effect.Effect<A1, E1, R1>) => Effect.Effect<A1, EW | E1, RW | R1>,
     }
 }
 
@@ -66,7 +68,7 @@ extends Pipeable.Class() implements LensWithInternals<A, ER, EW, RR, RW> {
     readonly get: Effect.Effect<A, ER, RR>
     readonly changes: Stream.Stream<A, ER, RR>
     readonly update: (a: A) => Effect.Effect<void, EW, RW>
-    readonly withLock: <A1, E1, R1>(self: Effect.Effect<A1, E1, R1>) => Effect.Effect<A1, E1, R1>
+    readonly withLock: <A1, E1, R1>(self: Effect.Effect<A1, E1, R1>) => Effect.Effect<A1, EW | E1, RW | R1>
 
     constructor(
         source: LensImpl.Source<A, ER, EW, RR, RW>
@@ -226,16 +228,10 @@ export const unwrap = <A, ER, EW, RR, RW, E1, R1>(
 ): Lens<A, ER | E1, EW | E1, RR | R1, RW | R1> => make({
     get: Effect.flatMap(effect, l => l.get),
     changes: Stream.unwrap(Effect.map(effect, l => l.changes)),
-    update: a => Effect.flatMap(
-        effect,
-        l => Effect.flatMap(asLensWithInternals(l), l => l.update(a))
-    ),
+    update: a => Effect.flatMap(effect, l => asLensWithInternals(l).update(a)),
     withLock: <A2, E2, R2>(
         effect2: Effect.Effect<A2, E2, R2>
-    ): Effect.Effect<A2, E1 | E2, R1 | R2> => Effect.flatMap(
-        effect,
-        l => Effect.flatMap(asLensWithInternals(l), l2 => l2.withLock(effect2)),
-    ),
+    ) => Effect.flatMap(effect, l => asLensWithInternals(l).withLock(effect2)),
 })
 
 /**
@@ -258,11 +254,8 @@ export const map: {
 ): Lens<B, ER, EW, RR, RW> => makeLazy({
     get get() { return Effect.map(self.get, get) },
     get changes() { return Stream.map(self.changes, get) },
-    modify: <C, E1 = never, R1 = never>(
-        f: (b: B) => Effect.Effect<readonly [C, B], E1, R1>
-    ) => self.modify(a =>
-        Effect.flatMap(f(get(a)), ([c, next]) => Effect.succeed([c, set(a, next)]))
-    ),
+    update(a: A) { return  },
+    get withLock() { return asLensWithInternals(self).withLock },
 }))
 
 /**