From 191105d2084337a5f5dac8231ece59aa9243abb1 Mon Sep 17 00:00:00 2001
From: Aarsh Duhlani <aarshduhlani05@gmail.com>
Date: Thu, 25 Jun 2026 04:28:58 +0530
Subject: [PATCH 1/3] fix(type): wire up type.fn.raw at runtime

type.fn.raw was typed but always undefined at runtime, so calling it threw
"type.fn.raw is not a function".

The parser read `$.fn` while building its `attach` object, but `$.fn` is the
InternalFnParser instance currently being constructed, so it was still
undefined and got captured as `raw`. Extract the parser into a local `parse`
function and reference it for both the callable body and `raw` so there's no
longer a dependency on the half-initialized scope.

Closes #1609
---
 ark/type/__tests__/fn.test.ts |  9 +++++++
 ark/type/fn.ts                | 48 ++++++++++++++++++-----------------
 2 files changed, 34 insertions(+), 23 deletions(-)

diff --git a/ark/type/__tests__/fn.test.ts b/ark/type/__tests__/fn.test.ts
index e8763e54d9..df293dc3c9 100644
--- a/ark/type/__tests__/fn.test.ts
+++ b/ark/type/__tests__/fn.test.ts
@@ -315,6 +315,15 @@ contextualize(() => {
 		attest(f.name).snap("bound typed originalName")
 	})
 
+	it("raw", () => {
+		const len = type.fn.raw("string | unknown[]")((s: string) => s.length)
+
+		attest(len("foo")).equals(3)
+		attest(() => len(1)).throws.snap(
+			"TraversalError: value at [0] must be a string or an object (was a number)"
+		)
+	})
+
 	it("arg submodule completions", () => {
 		// @ts-expect-error
 		attest(() => type.fn("string.nu")).completions({
diff --git a/ark/type/fn.ts b/ark/type/fn.ts
index 992eee80e8..39c0ef35da 100644
--- a/ark/type/fn.ts
+++ b/ark/type/fn.ts
@@ -73,35 +73,37 @@ type FnParserAttachments = Omit<FnParser, never>
 
 export class InternalFnParser extends Callable<(...args: unknown[]) => Fn> {
 	constructor($: InternalScope) {
-		const attach: FnParserAttachments = {
-			$: $ as never,
-			raw: $.fn
-		}
+		const parse = (...signature: unknown[]) => {
+			const returnOperatorIndex = signature.indexOf(":")
+			const lastParamIndex =
+				returnOperatorIndex === -1 ?
+					signature.length - 1
+				:	returnOperatorIndex - 1
 
-		super(
-			(...signature) => {
-				const returnOperatorIndex = signature.indexOf(":")
-				const lastParamIndex =
-					returnOperatorIndex === -1 ?
-						signature.length - 1
-					:	returnOperatorIndex - 1
+			const paramDefs = signature.slice(0, lastParamIndex + 1)
 
-				const paramDefs = signature.slice(0, lastParamIndex + 1)
+			const paramTuple = $.parse(paramDefs).assertHasKind("intersection")
 
-				const paramTuple = $.parse(paramDefs).assertHasKind("intersection")
+			let returnType: BaseRoot = $.intrinsic.unknown
+
+			if (returnOperatorIndex !== -1) {
+				if (returnOperatorIndex !== signature.length - 2)
+					return throwParseError(badFnReturnTypeMessage)
+				returnType = $.parse(signature[returnOperatorIndex + 1])
+			}
 
-				let returnType: BaseRoot = $.intrinsic.unknown
+			return (impl: Fn) => new InternalTypedFn(impl, paramTuple, returnType)
+		}
 
-				if (returnOperatorIndex !== -1) {
-					if (returnOperatorIndex !== signature.length - 2)
-						return throwParseError(badFnReturnTypeMessage)
-					returnType = $.parse(signature[returnOperatorIndex + 1])
-				}
+		// `raw` is an alias of `fn` itself with no type-level validation. It must
+		// reference `parse` directly rather than `$.fn`, which is still being
+		// constructed (and thus `undefined`) at this point.
+		const attach: FnParserAttachments = {
+			$: $ as never,
+			raw: parse
+		}
 
-				return (impl: Fn) => new InternalTypedFn(impl, paramTuple, returnType)
-			},
-			{ attach }
-		)
+		super(parse, { attach })
 	}
 }
 

From 9ba8bea566ffe6f6359407cd7247ebfee02ae5e3 Mon Sep 17 00:00:00 2001
From: Aarsh Duhlani <aarshduhlani05@gmail.com>
Date: Wed, 1 Jul 2026 19:30:47 +0530
Subject: [PATCH 2/3] fix(type): cast raw attachment to satisfy RawFnParser

---
 ark/type/fn.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ark/type/fn.ts b/ark/type/fn.ts
index 39c0ef35da..bd39724eed 100644
--- a/ark/type/fn.ts
+++ b/ark/type/fn.ts
@@ -100,7 +100,7 @@ export class InternalFnParser extends Callable<(...args: unknown[]) => Fn> {
 		// constructed (and thus `undefined`) at this point.
 		const attach: FnParserAttachments = {
 			$: $ as never,
-			raw: parse
+			raw: parse as never
 		}
 
 		super(parse, { attach })

From 54dce18f1a070f606859aac051b08cf8666c3881 Mon Sep 17 00:00:00 2001
From: Aarsh Duhlani <aarshduhlani05@gmail.com>
Date: Thu, 2 Jul 2026 17:14:44 +0530
Subject: [PATCH 3/3] test(type): annotate raw parser result which has no
 inference

---
 ark/type/__tests__/fn.test.ts | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/ark/type/__tests__/fn.test.ts b/ark/type/__tests__/fn.test.ts
index df293dc3c9..7b03486444 100644
--- a/ark/type/__tests__/fn.test.ts
+++ b/ark/type/__tests__/fn.test.ts
@@ -316,7 +316,10 @@ contextualize(() => {
 	})
 
 	it("raw", () => {
-		const len = type.fn.raw("string | unknown[]")((s: string) => s.length)
+		// raw has no type-level inference, so it's returned as an untyped parser
+		const len = type.fn.raw("string | unknown[]")((s: string) => s.length) as (
+			data: unknown
+		) => number
 
 		attest(len("foo")).equals(3)
 		attest(() => len(1)).throws.snap(