git.delta.rocks / jrsonnet / refs/commits / 78d82dfdf2a1

difftreelog

feat derive(Typed) for struct

Yaroslav Bolyukin2022-04-04parent: #d710b4f.patch.diff
in: master

9 files changed

modifiedCargo.lockdiffbeforeafterboth
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -70,8 +70,9 @@
 
 [[package]]
 name = "clap"
-version = "3.0.0-beta.2"
-source = "git+https://github.com/clap-rs/clap?rev=f0c5ea5e1503de5c8e74d8c047a799cf51498e83#f0c5ea5e1503de5c8e74d8c047a799cf51498e83"
+version = "3.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "71c47df61d9e16dc010b55dba1952a57d8c215dbb533fd13cdd13369aac73b1c"
 dependencies = [
  "atty",
  "bitflags",
@@ -82,27 +83,28 @@
  "strsim",
  "termcolor",
  "textwrap",
- "vec_map",
 ]
 
 [[package]]
+name = "clap_complete"
+version = "3.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "df6f3613c0a3cddfd78b41b10203eb322cb29b600cbdf808a7d3db95691b8e25"
+dependencies = [
+ "clap",
+]
+
+[[package]]
 name = "clap_derive"
-version = "3.0.0-beta.2"
-source = "git+https://github.com/clap-rs/clap?rev=f0c5ea5e1503de5c8e74d8c047a799cf51498e83#f0c5ea5e1503de5c8e74d8c047a799cf51498e83"
+version = "3.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a3aab4734e083b809aaf5794e14e756d1c798d2c69c7f7de7a09a2f5214993c1"
 dependencies = [
  "heck",
  "proc-macro-error",
  "proc-macro2",
  "quote",
  "syn",
-]
-
-[[package]]
-name = "clap_generate"
-version = "3.0.0-beta.2"
-source = "git+https://github.com/clap-rs/clap?rev=f0c5ea5e1503de5c8e74d8c047a799cf51498e83#f0c5ea5e1503de5c8e74d8c047a799cf51498e83"
-dependencies = [
- "clap",
 ]
 
 [[package]]
@@ -148,12 +150,9 @@
 
 [[package]]
 name = "heck"
-version = "0.3.3"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6d621efb26863f0e9924c6ac577e8275e5e6b77455db64ffa6c65c904e9e132c"
-dependencies = [
- "unicode-segmentation",
-]
+checksum = "2540771e65fc8cb83cd6e8a237f70c319bd5c29f78ed1084ba5d50eeac86f7f9"
 
 [[package]]
 name = "hermit-abi"
@@ -185,7 +184,7 @@
 version = "0.4.2"
 dependencies = [
  "clap",
- "clap_generate",
+ "clap_complete",
  "gcmodule",
  "jrsonnet-cli",
  "jrsonnet-evaluator",
@@ -214,6 +213,7 @@
  "bincode",
  "gcmodule",
  "jrsonnet-interner",
+ "jrsonnet-macros",
  "jrsonnet-parser",
  "jrsonnet-stdlib",
  "jrsonnet-types",
@@ -236,6 +236,15 @@
 ]
 
 [[package]]
+name = "jrsonnet-macros"
+version = "0.4.2"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
 name = "jrsonnet-parser"
 version = "0.4.2"
 dependencies = [
@@ -301,6 +310,12 @@
 checksum = "490cc448043f947bae3cbee9c203358d62dbee0db12107a74be5c30ccfd09771"
 
 [[package]]
+name = "memchr"
+version = "2.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "308cc39be01b73d0d18f82a0e7b2a3df85245f84af96fdddc5d202d27e47b86a"
+
+[[package]]
 name = "mimalloc-sys"
 version = "0.1.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -321,9 +336,12 @@
 
 [[package]]
 name = "os_str_bytes"
-version = "3.1.0"
+version = "6.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6acbef58a60fe69ab50510a55bc8cdd4d6cf2283d27ad338f54cb52747a9cf2d"
+checksum = "8e22443d1643a904602595ba1cd8f7d896afe56d26712531c5ff73a15b2fbf64"
+dependencies = [
+ "memchr",
+]
 
 [[package]]
 name = "parking_lot"
@@ -357,9 +375,9 @@
 
 [[package]]
 name = "peg"
-version = "0.7.0"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "07c0b841ea54f523f7aa556956fbd293bcbe06f2e67d2eb732b7278aaf1d166a"
+checksum = "af728fe826811af3b38c37e93de6d104485953ea373d656eebae53d6987fcd2c"
 dependencies = [
  "peg-macros",
  "peg-runtime",
@@ -367,9 +385,9 @@
 
 [[package]]
 name = "peg-macros"
-version = "0.7.0"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b5aa52829b8decbef693af90202711348ab001456803ba2a98eb4ec8fb70844c"
+checksum = "4536be147b770b824895cbad934fccce8e49f14b4c4946eaa46a6e4a12fcdc16"
 dependencies = [
  "peg-runtime",
  "proc-macro2",
@@ -378,9 +396,9 @@
 
 [[package]]
 name = "peg-runtime"
-version = "0.7.0"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c719dcf55f09a3a7e764c6649ab594c18a177e3599c467983cdf644bfc0a4088"
+checksum = "f9b0efd3ba03c3a409d44d60425f279ec442bcf0b9e63ff4e410da31c8b0f69f"
 
 [[package]]
 name = "proc-macro-error"
@@ -536,12 +554,9 @@
 
 [[package]]
 name = "textwrap"
-version = "0.14.2"
+version = "0.15.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0066c8d12af8b5acd21e00547c3797fde4e8677254a7ee429176ccebbe93dd80"
-dependencies = [
- "unicode-width",
-]
+checksum = "b1141d4d61095b28419e22cb0bbf02755f5e54e0526f97f1e3d1d160e60885fb"
 
 [[package]]
 name = "thiserror"
@@ -562,12 +577,6 @@
  "quote",
  "syn",
 ]
-
-[[package]]
-name = "unicode-segmentation"
-version = "1.8.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8895849a949e7845e06bd6dc1aa51731a103c42707010a5b591c0038fb73385b"
 
 [[package]]
 name = "unicode-width"
@@ -580,12 +589,6 @@
 version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8ccb82d61f80a663efe1f787a51b16b5a51e3314d6ac365b08639f52387b33f3"
-
-[[package]]
-name = "vec_map"
-version = "0.8.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f1bddf1187be692e79c5ffeab891132dfb0f236ed36a43c7ed39f1165ee20191"
 
 [[package]]
 name = "version_check"
modifiedcrates/jrsonnet-evaluator/src/error.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/error.rs
+++ b/crates/jrsonnet-evaluator/src/error.rs
@@ -179,7 +179,7 @@
 	}
 }
 
-pub type Result<V> = std::result::Result<V, LocError>;
+pub type Result<V, E = LocError> = std::result::Result<V, E>;
 
 #[macro_export]
 macro_rules! throw {
modifiedcrates/jrsonnet-evaluator/src/function.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/function.rs
+++ b/crates/jrsonnet-evaluator/src/function.rs
@@ -8,6 +8,7 @@
 };
 use gcmodule::Trace;
 use jrsonnet_interner::IStr;
+pub use jrsonnet_macros::builtin;
 use jrsonnet_parser::{ArgsDesc, ExprLocation, LocExpr, ParamsDesc};
 use std::{borrow::Cow, collections::HashMap, convert::TryFrom};
 
@@ -377,6 +378,7 @@
 	pub has_default: bool,
 }
 
+/// Do not implement it directly, instead use #[builtin] macro
 pub trait Builtin: Trace {
 	fn name(&self) -> &str;
 	fn params(&self) -> &[BuiltinParam];
modifiedcrates/jrsonnet-evaluator/src/lib.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/lib.rs
+++ b/crates/jrsonnet-evaluator/src/lib.rs
@@ -174,7 +174,11 @@
 	pub(crate) static EVAL_STATE: RefCell<Option<EvaluationState>> = RefCell::new(None)
 }
 pub(crate) fn with_state<T>(f: impl FnOnce(&EvaluationState) -> T) -> T {
-	EVAL_STATE.with(|s| f(s.borrow().as_ref().unwrap()))
+	EVAL_STATE.with(|s| {
+		f(s.borrow().as_ref().expect(
+			"missing evaluation state, some functions should be called inside of run_in_state call",
+		))
+	})
 }
 pub fn push_frame<T>(
 	e: Option<&ExprLocation>,
@@ -728,12 +732,15 @@
 	}
 
 	macro_rules! eval {
-		($str: expr) => {
-			EvaluationState::default()
-				.with_stdlib()
-				.evaluate_snippet_raw(PathBuf::from("raw.jsonnet").into(), $str.into())
-				.unwrap()
-		};
+		($str: expr) => {{
+			let evaluator = EvaluationState::default();
+			evaluator.with_stdlib();
+			evaluator.run_in_state(|| {
+				evaluator
+					.evaluate_snippet_raw(PathBuf::from("raw.jsonnet").into(), $str.into())
+					.unwrap()
+			})
+		}};
 	}
 	macro_rules! eval_json {
 		($str: expr) => {{
@@ -1265,4 +1272,47 @@
 		assert_eval!(r#"std.assertEqual(std.count(["a", "b", "a"], "d"), 0)"#);
 		assert_eval!(r#"std.assertEqual(std.count(["a", "b", "a"], "a"), 2)"#);
 	}
+
+	mod derive_typed {
+		use crate::{typed::Typed, EvaluationState};
+		use std::path::PathBuf;
+
+		#[derive(Typed, PartialEq, Debug)]
+		struct MyTyped {
+			a: u32,
+			b: String,
+		}
+
+		#[test]
+		fn test() {
+			let es = EvaluationState::default();
+			let val = eval!("{a: 14, b: 'Hello, world!'}");
+			let typed = es.run_in_state(|| MyTyped::try_from(val).unwrap());
+
+			assert_eq!(
+				typed,
+				MyTyped {
+					a: 14,
+					b: "Hello, world!".to_string()
+				}
+			);
+			es.settings_mut().globals.insert(
+				"mytyped".into(),
+				es.run_in_state(|| typed.try_into()).unwrap(),
+			);
+
+			let v = es
+				.evaluate_snippet_raw(
+					PathBuf::from("raw.jsonnet").into(),
+					"
+				mytyped == {a: 14, b: 'Hello, world!'}
+			"
+					.into(),
+				)
+				.unwrap()
+				.as_bool()
+				.unwrap();
+			assert!(v)
+		}
+	}
 }
modifiedcrates/jrsonnet-evaluator/src/typed/conversions.rsdiffbeforeafterboth
before · crates/jrsonnet-evaluator/src/typed/conversions.rs
1use std::convert::{TryFrom, TryInto};23use jrsonnet_interner::IStr;4use jrsonnet_types::{ComplexValType, ValType};56use crate::{7	error::{Error::*, LocError, Result},8	throw,9	typed::CheckType,10	ArrValue, FuncVal, IndexableVal, ObjValue, Val,11};1213pub trait Typed: TryFrom<Val, Error = LocError> + TryInto<Val, Error = LocError> {14	const TYPE: &'static ComplexValType;15}1617macro_rules! impl_int {18	($($ty:ty)*) => {$(19		impl Typed for $ty {20			const TYPE: &'static ComplexValType =21				&ComplexValType::BoundedNumber(Some(Self::MIN as f64), Some(Self::MAX as f64));22		}23		impl TryFrom<Val> for $ty {24			type Error = LocError;2526			fn try_from(value: Val) -> Result<Self> {27				<Self as Typed>::TYPE.check(&value)?;28				match value {29					Val::Num(n) => {30						if n.trunc() != n {31							throw!(RuntimeError(32								format!(33									"cannot convert number with fractional part to {}",34									stringify!($ty)35								)36								.into()37							))38						}39						Ok(n as Self)40					}41					_ => unreachable!(),42				}43			}44		}45		impl TryFrom<$ty> for Val {46			type Error = LocError;4748			fn try_from(value: $ty) -> Result<Self> {49				Ok(Self::Num(value as f64))50			}51		}52	)*};53}5455impl_int!(i8 u8 i16 u16 i32 u32);5657impl Typed for f64 {58	const TYPE: &'static ComplexValType = &ComplexValType::Simple(ValType::Num);59}60impl TryFrom<Val> for f64 {61	type Error = LocError;6263	fn try_from(value: Val) -> Result<Self> {64		<Self as Typed>::TYPE.check(&value)?;65		match value {66			Val::Num(n) => Ok(n),67			_ => unreachable!(),68		}69	}70}71impl TryFrom<f64> for Val {72	type Error = LocError;7374	fn try_from(value: f64) -> Result<Self> {75		Ok(Self::Num(value))76	}77}7879pub struct PositiveF64(pub f64);80impl Typed for PositiveF64 {81	const TYPE: &'static ComplexValType = &ComplexValType::BoundedNumber(Some(0.0), None);82}83impl TryFrom<Val> for PositiveF64 {84	type Error = LocError;8586	fn try_from(value: Val) -> Result<Self> {87		<Self as Typed>::TYPE.check(&value)?;88		match value {89			Val::Num(n) => Ok(Self(n)),90			_ => unreachable!(),91		}92	}93}94impl TryFrom<PositiveF64> for Val {95	type Error = LocError;9697	fn try_from(value: PositiveF64) -> Result<Self> {98		Ok(Self::Num(value.0))99	}100}101102impl Typed for usize {103	// It is possible to store 54 bits of precision in f64, but leaving u32::MAX here for compatibility104	const TYPE: &'static ComplexValType =105		&ComplexValType::BoundedNumber(Some(0.0), Some(4294967295.0));106}107impl TryFrom<Val> for usize {108	type Error = LocError;109110	fn try_from(value: Val) -> Result<Self> {111		<Self as Typed>::TYPE.check(&value)?;112		match value {113			Val::Num(n) => {114				if n.trunc() != n {115					throw!(RuntimeError(116						"cannot convert number with fractional part to usize".into()117					))118				}119				Ok(n as Self)120			}121			_ => unreachable!(),122		}123	}124}125impl TryFrom<usize> for Val {126	type Error = LocError;127128	fn try_from(value: usize) -> Result<Self> {129		if value > u32::MAX as usize {130			throw!(RuntimeError("number is too large".into()))131		}132		Ok(Self::Num(value as f64))133	}134}135136impl Typed for IStr {137	const TYPE: &'static ComplexValType = &ComplexValType::Simple(ValType::Str);138}139impl TryFrom<Val> for IStr {140	type Error = LocError;141142	fn try_from(value: Val) -> Result<Self> {143		<Self as Typed>::TYPE.check(&value)?;144		match value {145			Val::Str(s) => Ok(s),146			_ => unreachable!(),147		}148	}149}150impl TryFrom<IStr> for Val {151	type Error = LocError;152153	fn try_from(value: IStr) -> Result<Self> {154		Ok(Self::Str(value))155	}156}157158impl Typed for String {159	const TYPE: &'static ComplexValType = &ComplexValType::Simple(ValType::Str);160}161impl TryFrom<Val> for String {162	type Error = LocError;163164	fn try_from(value: Val) -> Result<Self> {165		<Self as Typed>::TYPE.check(&value)?;166		match value {167			Val::Str(s) => Ok(s.to_string()),168			_ => unreachable!(),169		}170	}171}172impl TryFrom<String> for Val {173	type Error = LocError;174175	fn try_from(value: String) -> Result<Self> {176		Ok(Self::Str(value.into()))177	}178}179180impl Typed for char {181	const TYPE: &'static ComplexValType = &ComplexValType::Char;182}183impl TryFrom<Val> for char {184	type Error = LocError;185186	fn try_from(value: Val) -> Result<Self> {187		<Self as Typed>::TYPE.check(&value)?;188		match value {189			Val::Str(s) => Ok(s.chars().next().unwrap()),190			_ => unreachable!(),191		}192	}193}194impl TryFrom<char> for Val {195	type Error = LocError;196197	fn try_from(value: char) -> Result<Self> {198		Ok(Self::Str(value.to_string().into()))199	}200}201202impl<T> Typed for Vec<T>203where204	T: Typed,205	T: TryFrom<Val, Error = LocError>,206	T: TryInto<Val, Error = LocError>,207{208	const TYPE: &'static ComplexValType = &ComplexValType::ArrayRef(T::TYPE);209}210impl<T> TryFrom<Val> for Vec<T>211where212	T: Typed,213	T: TryFrom<Val, Error = LocError>,214	T: TryInto<Val, Error = LocError>,215{216	type Error = LocError;217218	fn try_from(value: Val) -> Result<Self> {219		<Self as Typed>::TYPE.check(&value)?;220		match value {221			Val::Arr(a) => {222				let mut o = Self::with_capacity(a.len());223				for i in a.iter() {224					o.push(T::try_from(i?)?);225				}226				Ok(o)227			}228			_ => unreachable!(),229		}230	}231}232impl<T> TryFrom<Vec<T>> for Val233where234	T: Typed,235	T: TryFrom<Self, Error = LocError>,236	T: TryInto<Self, Error = LocError>,237{238	type Error = LocError;239240	fn try_from(value: Vec<T>) -> Result<Self> {241		let mut o = Vec::with_capacity(value.len());242		for i in value {243			o.push(i.try_into()?);244		}245		Ok(Self::Arr(o.into()))246	}247}248249/// To be used in Vec<Any>250/// Regular Val can't be used here, because it has wrong TryFrom::Error type251#[derive(Clone)]252pub struct Any(pub Val);253254impl Typed for Any {255	const TYPE: &'static ComplexValType = &ComplexValType::Any;256}257impl TryFrom<Val> for Any {258	type Error = LocError;259260	fn try_from(value: Val) -> Result<Self> {261		Ok(Self(value))262	}263}264impl TryFrom<Any> for Val {265	type Error = LocError;266267	fn try_from(value: Any) -> Result<Self> {268		Ok(value.0)269	}270}271272/// Specialization, provides faster TryFrom<VecVal> for Val273pub struct VecVal(pub Vec<Val>);274275impl Typed for VecVal {276	const TYPE: &'static ComplexValType = &ComplexValType::Simple(ValType::Arr);277}278impl TryFrom<Val> for VecVal {279	type Error = LocError;280281	fn try_from(value: Val) -> Result<Self> {282		<Self as Typed>::TYPE.check(&value)?;283		match value {284			Val::Arr(a) => Ok(Self(a.evaluated()?.to_vec())),285			_ => unreachable!(),286		}287	}288}289impl TryFrom<VecVal> for Val {290	type Error = LocError;291292	fn try_from(value: VecVal) -> Result<Self> {293		Ok(Self::Arr(value.0.into()))294	}295}296297pub struct M1;298impl Typed for M1 {299	const TYPE: &'static ComplexValType = &ComplexValType::BoundedNumber(Some(-1.0), Some(-1.0));300}301impl TryFrom<Val> for M1 {302	type Error = LocError;303304	fn try_from(value: Val) -> Result<Self> {305		<Self as Typed>::TYPE.check(&value)?;306		Ok(Self)307	}308}309impl TryFrom<M1> for Val {310	type Error = LocError;311312	fn try_from(_: M1) -> Result<Self> {313		Ok(Self::Num(-1.0))314	}315}316317macro_rules! decl_either {318	($($name: ident, $($id: ident)*);*) => {$(319		pub enum $name<$($id),*> {320			$($id($id)),*321		}322		impl<$($id),*> Typed for $name<$($id),*>323		where324			$($id: Typed,)*325		{326			const TYPE: &'static ComplexValType = &ComplexValType::UnionRef(&[$($id::TYPE),*]);327		}328		impl<$($id),*> TryFrom<Val> for $name<$($id),*>329		where330			$($id: Typed,)*331		{332			type Error = LocError;333334			fn try_from(value: Val) -> Result<Self> {335				$(336					if $id::TYPE.check(&value).is_ok() {337						$id::try_from(value).map(Self::$id)338					} else339				)* {340					<Self as Typed>::TYPE.check(&value)?;341					unreachable!()342				}343			}344		}345		impl<$($id),*> TryFrom<$name<$($id),*>> for Val346		where347			$($id: Typed,)*348		{349			type Error = LocError;350			fn try_from(value: $name<$($id),*>) -> Result<Self> {351				match value {$(352					$name::$id(v) => v.try_into()353				),*}354			}355		}356	)*}357}358decl_either!(359	Either1, A;360	Either2, A B;361	Either3, A B C;362	Either4, A B C D;363	Either5, A B C D E;364	Either6, A B C D E F;365	Either7, A B C D E F G366);367#[macro_export]368macro_rules! Either {369	($a:ty) => {Either1<$a>};370	($a:ty, $b:ty) => {Either2<$a, $b>};371	($a:ty, $b:ty, $c:ty) => {Either3<$a, $b, $c>};372	($a:ty, $b:ty, $c:ty, $d:ty) => {Either4<$a, $b, $c, $d>};373	($a:ty, $b:ty, $c:ty, $d:ty, $e:ty) => {Either5<$a, $b, $c, $d, $e>};374	($a:ty, $b:ty, $c:ty, $d:ty, $e:ty, $f:ty) => {Either6<$a, $b, $c, $d, $e, $f>};375	($a:ty, $b:ty, $c:ty, $d:ty, $e:ty, $f:ty, $g:ty) => {Either7<$a, $b, $c, $d, $e, $f, $g>};376}377378pub type MyType = Either![u32, f64, String];379380impl Typed for ArrValue {381	const TYPE: &'static ComplexValType = &ComplexValType::Simple(ValType::Arr);382}383impl TryFrom<Val> for ArrValue {384	type Error = LocError;385386	fn try_from(value: Val) -> Result<Self> {387		<Self as Typed>::TYPE.check(&value)?;388		match value {389			Val::Arr(a) => Ok(a),390			_ => unreachable!(),391		}392	}393}394impl TryFrom<ArrValue> for Val {395	type Error = LocError;396397	fn try_from(value: ArrValue) -> Result<Self> {398		Ok(Self::Arr(value))399	}400}401402impl Typed for FuncVal {403	const TYPE: &'static ComplexValType = &ComplexValType::Simple(ValType::Func);404}405impl TryFrom<Val> for FuncVal {406	type Error = LocError;407408	fn try_from(value: Val) -> Result<Self> {409		<Self as Typed>::TYPE.check(&value)?;410		match value {411			Val::Func(a) => Ok(a),412			_ => unreachable!(),413		}414	}415}416impl TryFrom<FuncVal> for Val {417	type Error = LocError;418419	fn try_from(value: FuncVal) -> Result<Self> {420		Ok(Self::Func(value))421	}422}423impl Typed for ObjValue {424	const TYPE: &'static ComplexValType = &ComplexValType::Simple(ValType::Obj);425}426impl TryFrom<Val> for ObjValue {427	type Error = LocError;428429	fn try_from(value: Val) -> Result<Self> {430		<Self as Typed>::TYPE.check(&value)?;431		match value {432			Val::Obj(a) => Ok(a),433			_ => unreachable!(),434		}435	}436}437impl TryFrom<ObjValue> for Val {438	type Error = LocError;439440	fn try_from(value: ObjValue) -> Result<Self> {441		Ok(Self::Obj(value))442	}443}444445impl Typed for bool {446	const TYPE: &'static ComplexValType = &ComplexValType::Simple(ValType::Bool);447}448impl TryFrom<Val> for bool {449	type Error = LocError;450451	fn try_from(value: Val) -> Result<Self> {452		<Self as Typed>::TYPE.check(&value)?;453		match value {454			Val::Bool(a) => Ok(a),455			_ => unreachable!(),456		}457	}458}459impl TryFrom<bool> for Val {460	type Error = LocError;461462	fn try_from(value: bool) -> Result<Self> {463		Ok(Self::Bool(value))464	}465}466467impl Typed for IndexableVal {468	const TYPE: &'static ComplexValType = &ComplexValType::UnionRef(&[469		&ComplexValType::Simple(ValType::Arr),470		&ComplexValType::Simple(ValType::Str),471	]);472}473impl TryFrom<Val> for IndexableVal {474	type Error = LocError;475476	fn try_from(value: Val) -> Result<Self> {477		<Self as Typed>::TYPE.check(&value)?;478		value.into_indexable()479	}480}481impl TryFrom<IndexableVal> for Val {482	type Error = LocError;483484	fn try_from(value: IndexableVal) -> Result<Self> {485		match value {486			IndexableVal::Str(s) => Ok(Self::Str(s)),487			IndexableVal::Arr(a) => Ok(Self::Arr(a)),488		}489	}490}491492pub struct Null;493impl Typed for Null {494	const TYPE: &'static ComplexValType = &ComplexValType::Simple(ValType::Null);495}496impl TryFrom<Val> for Null {497	type Error = LocError;498499	fn try_from(value: Val) -> Result<Self> {500		<Self as Typed>::TYPE.check(&value)?;501		Ok(Self)502	}503}504impl TryFrom<Null> for Val {505	type Error = LocError;506507	fn try_from(_: Null) -> Result<Self> {508		Ok(Self::Null)509	}510}
modifiedcrates/jrsonnet-evaluator/src/typed/mod.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/typed/mod.rs
+++ b/crates/jrsonnet-evaluator/src/typed/mod.rs
@@ -8,20 +8,8 @@
 	push_description_frame, Val,
 };
 use gcmodule::Trace;
-use jrsonnet_types::{ComplexValType, ValType};
+pub use jrsonnet_types::{ComplexValType, ValType};
 use thiserror::Error;
-
-#[macro_export]
-macro_rules! unwrap_type {
-	($desc:expr, $value:expr, $typ:expr => $match:path) => {{
-		use $crate::{push_frame, typed::CheckType};
-		push_frame(None, $desc, || Ok($typ.check(&$value)?))?;
-		match $value {
-			$match(v) => v,
-			_ => unreachable!(),
-		}
-	}};
-}
 
 #[derive(Debug, Error, Clone, Trace)]
 pub enum TypeError {
@@ -136,7 +124,7 @@
 impl Display for ValuePathItem {
 	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 		match self {
-			Self::Field(name) => write!(f, ".{}", name)?,
+			Self::Field(name) => write!(f, ".{:?}", name)?,
 			Self::Index(idx) => write!(f, "[{}]", idx)?,
 		}
 		Ok(())
modifiedcrates/jrsonnet-evaluator/src/val.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/val.rs
+++ b/crates/jrsonnet-evaluator/src/val.rs
@@ -91,7 +91,7 @@
 	Normal(Cc<FuncDesc>),
 	/// Standard library function
 	StaticBuiltin(#[skip_trace] &'static dyn StaticBuiltin),
-
+	/// User-provided function
 	Builtin(Cc<TraceBox<dyn Builtin>>),
 }
 
@@ -99,8 +99,10 @@
 	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 		match self {
 			Self::Normal(arg0) => f.debug_tuple("Normal").field(arg0).finish(),
-			Self::StaticBuiltin(arg0) => f.debug_tuple("Intrinsic").field(&arg0.name()).finish(),
-			Self::Builtin(arg0) => f.debug_tuple("Intrinsic").field(&arg0.name()).finish(),
+			Self::StaticBuiltin(arg0) => {
+				f.debug_tuple("StaticBuiltin").field(&arg0.name()).finish()
+			}
+			Self::Builtin(arg0) => f.debug_tuple("Builtin").field(&arg0.name()).finish(),
 		}
 	}
 }
@@ -338,6 +340,49 @@
 }
 
 impl Val {
+	pub fn as_bool(&self) -> Option<bool> {
+		match self {
+			Val::Bool(v) => Some(*v),
+			_ => None,
+		}
+	}
+	pub fn as_null(&self) -> Option<()> {
+		match self {
+			Val::Null => Some(()),
+			_ => None,
+		}
+	}
+	pub fn as_str(&self) -> Option<IStr> {
+		match self {
+			Val::Str(s) => Some(s.clone()),
+			_ => None,
+		}
+	}
+	pub fn as_num(&self) -> Option<f64> {
+		match self {
+			Val::Num(n) => Some(*n),
+			_ => None,
+		}
+	}
+	pub fn as_arr(&self) -> Option<ArrValue> {
+		match self {
+			Val::Arr(a) => Some(a.clone()),
+			_ => None,
+		}
+	}
+	pub fn as_obj(&self) -> Option<ObjValue> {
+		match self {
+			Val::Obj(o) => Some(o.clone()),
+			_ => None,
+		}
+	}
+	pub fn as_func(&self) -> Option<FuncVal> {
+		match self {
+			Val::Func(f) => Some(f.clone()),
+			_ => None,
+		}
+	}
+
 	/// Creates `Val::Num` after checking for numeric overflow.
 	/// As numbers are `f64`, we can just check for their finity.
 	pub fn new_checked_num(num: f64) -> Result<Self> {
modifiedcrates/jrsonnet-macros/src/lib.rsdiffbeforeafterboth
--- a/crates/jrsonnet-macros/src/lib.rs
+++ b/crates/jrsonnet-macros/src/lib.rs
@@ -1,8 +1,8 @@
 use quote::{quote, quote_spanned};
 use syn::{
 	parenthesized, parse::Parse, parse_macro_input, punctuated::Punctuated, spanned::Spanned,
-	token::Comma, FnArg, GenericArgument, Ident, ItemFn, Pat, PatType, Path, PathArguments, Token,
-	Type,
+	token::Comma, DeriveInput, FnArg, GenericArgument, Ident, ItemFn, Pat, PatType, Path,
+	PathArguments, Token, Type,
 };
 
 fn is_location_arg(t: &PatType) -> bool {
@@ -254,3 +254,86 @@
 	})
 	.into()
 }
+
+#[proc_macro_derive(Typed)]
+pub fn derive_typed(item: proc_macro::TokenStream) -> proc_macro::TokenStream {
+	let input = parse_macro_input!(item as DeriveInput);
+	let data = match &input.data {
+		syn::Data::Struct(s) => s,
+		_ => {
+			return syn::Error::new(input.span(), "only structs supported")
+				.to_compile_error()
+				.into()
+		}
+	};
+
+	let ident = &input.ident;
+
+	let fields_def = data.fields.iter().map(|f| {
+		let name = f
+			.ident
+			.as_ref()
+			.expect("only named fields supported")
+			.to_string();
+		let ty = &f.ty;
+		quote! {
+			(#name, #ty::TYPE),
+		}
+	});
+	let fields_parse = data.fields.iter().map(|f| {
+		let ident = f.ident.as_ref().unwrap();
+		let name = ident.to_string();
+		let ty = &f.ty;
+		quote! {
+			#ident: #ty::try_from(obj.get(#name.into())?.expect("shape is correct"))?,
+		}
+	});
+	let fields_serialize = data.fields.iter().map(|f| {
+		let ident = f.ident.as_ref().unwrap();
+		let name = ident.to_string();
+		quote! {
+			out.member(#name.into()).value(self.#ident.try_into()?);
+		}
+	});
+	let field_count = data.fields.len();
+
+	quote! {
+		const _: () = {
+			use ::jrsonnet_evaluator::{
+				typed::{ComplexValType, Typed, CheckType},
+				Val,
+				error::LocError,
+				obj::ObjValueBuilder,
+			};
+
+			const ITEMS: [(&'static str, &'static ComplexValType); #field_count] = [
+				#(#fields_def)*
+			];
+			impl Typed for #ident {
+				const TYPE: &'static ComplexValType = &ComplexValType::ObjectRef(&ITEMS);
+			}
+
+			impl TryFrom<Val> for #ident {
+				type Error = LocError;
+				fn try_from(value: Val) -> Result<Self, Self::Error> {
+					<Self as Typed>::TYPE.check(&value)?;
+					let obj = value.as_obj().expect("shape is correct");
+
+					Ok(Self {
+						#(#fields_parse)*
+					})
+				}
+			}
+			impl TryInto<Val> for #ident {
+				type Error = LocError;
+				fn try_into(self) -> Result<Val, Self::Error> {
+					let mut out = ObjValueBuilder::new();
+					#(#fields_serialize)*
+					Ok(Val::Obj(out.build()))
+				}
+			}
+			()
+		};
+	}
+	.into()
+}
modifiedcrates/jrsonnet-types/src/lib.rsdiffbeforeafterboth
--- a/crates/jrsonnet-types/src/lib.rs
+++ b/crates/jrsonnet-types/src/lib.rs
@@ -122,7 +122,7 @@
 	BoundedNumber(Option<f64>, Option<f64>),
 	Array(Box<ComplexValType>),
 	ArrayRef(&'static ComplexValType),
-	ObjectRef(&'static [(&'static str, ComplexValType)]),
+	ObjectRef(&'static [(&'static str, &'static ComplexValType)]),
 	Union(Vec<ComplexValType>),
 	UnionRef(&'static [&'static ComplexValType]),
 	Sum(Vec<ComplexValType>),