git.delta.rocks / jrsonnet / refs/commits / 349c41065b93

difftreelog

feat lazy values in builtin

Yaroslav Bolyukin2022-04-20parent: #c7fb888.patch.diff
in: master

8 files changed

modifiedcrates/jrsonnet-evaluator/src/builtin/mod.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/builtin/mod.rs
+++ b/crates/jrsonnet-evaluator/src/builtin/mod.rs
@@ -1,4 +1,4 @@
-use crate::function::StaticBuiltin;
+use crate::function::{CallLocation, StaticBuiltin};
 use crate::typed::{Any, PositiveF64, VecVal, M1};
 use crate::{
 	builtin::manifest::{manifest_yaml_ex, ManifestYamlOptions},
@@ -12,7 +12,6 @@
 use crate::{Either, ObjValue};
 use format::{format_arr, format_obj};
 use jrsonnet_interner::IStr;
-use jrsonnet_parser::ExprLocation;
 use serde::Deserialize;
 use serde_yaml::DeserializingQuirks;
 use std::collections::HashMap;
@@ -29,7 +28,7 @@
 
 pub fn std_format(str: IStr, vals: Val) -> Result<String> {
 	push_frame(
-		None,
+		CallLocation::native(),
 		|| format!("std.format of {}", str),
 		|| {
 			Ok(match vals {
@@ -467,9 +466,9 @@
 }
 
 #[jrsonnet_macros::builtin]
-fn builtin_trace(#[location] loc: Option<&ExprLocation>, str: IStr, rest: Any) -> Result<Any> {
+fn builtin_trace(loc: CallLocation, str: IStr, rest: Any) -> Result<Any> {
 	eprint!("TRACE:");
-	if let Some(loc) = loc {
+	if let Some(loc) = loc.0 {
 		with_state(|s| {
 			let locs = s.map_source_locations(&loc.0, &[loc.1]);
 			eprint!(
modifiedcrates/jrsonnet-evaluator/src/evaluate/mod.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/evaluate/mod.rs
+++ b/crates/jrsonnet-evaluator/src/evaluate/mod.rs
@@ -4,6 +4,7 @@
 	builtin::{std_slice, BUILTINS},
 	error::Error::*,
 	evaluate::operator::{evaluate_add_op, evaluate_binary_op_special, evaluate_unary_op},
+	function::CallLocation,
 	gc::TraceBox,
 	push_frame, throw, with_state, ArrValue, Bindable, Context, ContextCreator, FuncDesc, FuncVal,
 	FutureWrapper, GcHashMap, LazyBinding, LazyVal, LazyValValue, ObjValue, ObjValueBuilder,
@@ -12,8 +13,8 @@
 use gcmodule::{Cc, Trace};
 use jrsonnet_interner::IStr;
 use jrsonnet_parser::{
-	ArgsDesc, AssertStmt, BindSpec, CompSpec, Expr, ExprLocation, FieldMember, ForSpecData,
-	IfSpecData, LiteralType, LocExpr, Member, ObjBody, ParamsDesc,
+	ArgsDesc, AssertStmt, BindSpec, CompSpec, Expr, FieldMember, ForSpecData, IfSpecData,
+	LiteralType, LocExpr, Member, ObjBody, ParamsDesc,
 };
 use jrsonnet_types::ValType;
 pub mod operator;
@@ -192,7 +193,7 @@
 	Ok(match field_name {
 		jrsonnet_parser::FieldName::Fixed(n) => Some(n.clone()),
 		jrsonnet_parser::FieldName::Dyn(expr) => push_frame(
-			Some(&expr.1),
+			CallLocation::new(&expr.1),
 			|| "evaluating field name".to_string(),
 			|| {
 				let value = evaluate(context, expr)?;
@@ -442,7 +443,7 @@
 	context: Context,
 	value: &LocExpr,
 	args: &ArgsDesc,
-	loc: Option<&ExprLocation>,
+	loc: CallLocation,
 	tailstrict: bool,
 ) -> Result<Val> {
 	let value = evaluate(context.clone(), value)?;
@@ -463,13 +464,13 @@
 	let value = &assertion.0;
 	let msg = &assertion.1;
 	let assertion_result = push_frame(
-		Some(&value.1),
+		CallLocation::new(&value.1),
 		|| "assertion condition".to_owned(),
 		|| bool::try_from(evaluate(context.clone(), value)?),
 	)?;
 	if !assertion_result {
 		push_frame(
-			Some(&value.1),
+			CallLocation::new(&value.1),
 			|| "assertion failure".to_owned(),
 			|| {
 				if let Some(msg) = msg {
@@ -519,7 +520,7 @@
 		BinaryOp(v1, o, v2) => evaluate_binary_op_special(context, v1, *o, v2)?,
 		UnaryOp(o, v) => evaluate_unary_op(*o, &evaluate(context, v)?)?,
 		Var(name) => push_frame(
-			Some(loc),
+			CallLocation::new(loc),
 			|| format!("variable <{}> access", name),
 			|| context.binding(name.clone())?.evaluate(),
 		)?,
@@ -528,7 +529,7 @@
 				(Val::Obj(v), Val::Str(s)) => {
 					let sn = s.clone();
 					push_frame(
-						Some(loc),
+						CallLocation::new(loc),
 						|| format!("field <{}> access", sn),
 						|| {
 							if let Some(v) = v.get(s.clone())? {
@@ -625,7 +626,7 @@
 			&Val::Obj(evaluate_object(context, t)?),
 		)?,
 		Apply(value, args, tailstrict) => {
-			evaluate_apply(context, value, args, Some(loc), *tailstrict)?
+			evaluate_apply(context, value, args, CallLocation::new(loc), *tailstrict)?
 		}
 		Function(params, body) => {
 			evaluate_method(context, "anonymous".into(), params.clone(), body.clone())
@@ -640,7 +641,7 @@
 			evaluate(context, returned)?
 		}
 		ErrorStmt(e) => push_frame(
-			Some(loc),
+			CallLocation::new(loc),
 			|| "error statement".to_owned(),
 			|| throw!(RuntimeError(IStr::try_from(evaluate(context, e)?)?,)),
 		)?,
@@ -650,7 +651,7 @@
 			cond_else,
 		} => {
 			if push_frame(
-				Some(loc),
+				CallLocation::new(loc),
 				|| "if condition".to_owned(),
 				|| bool::try_from(evaluate(context.clone(), &cond.0)?),
 			)? {
@@ -689,7 +690,7 @@
 			let mut import_location = tmp.to_path_buf();
 			import_location.pop();
 			push_frame(
-				Some(loc),
+				CallLocation::new(loc),
 				|| format!("import {:?}", path),
 				|| with_state(|s| s.import_file(&import_location, path)),
 			)?
modifiedcrates/jrsonnet-evaluator/src/function.rsdiffbeforeafterboth
after · crates/jrsonnet-evaluator/src/function.rs
1use crate::{2	error::{Error::*, LocError},3	evaluate, evaluate_named,4	gc::TraceBox,5	throw,6	typed::Typed,7	Context, FutureWrapper, GcHashMap, LazyVal, LazyValValue, Result, Val,8};9use gcmodule::Trace;10use jrsonnet_interner::IStr;11pub use jrsonnet_macros::builtin;12use jrsonnet_parser::{ArgsDesc, ExprLocation, LocExpr, ParamsDesc};13use std::{borrow::Cow, collections::HashMap, convert::TryFrom};1415#[derive(Clone, Copy)]16pub struct CallLocation<'l>(pub Option<&'l ExprLocation>);17impl<'l> CallLocation<'l> {18	pub fn new(loc: &'l ExprLocation) -> Self {19		Self(Some(loc))20	}21}22impl CallLocation<'static> {23	pub fn native() -> Self {24		Self(None)25	}26}2728#[derive(Trace)]29struct EvaluateLazyVal {30	context: Context,31	expr: LocExpr,32}33impl LazyValValue for EvaluateLazyVal {34	fn get(self: Box<Self>) -> Result<Val> {35		evaluate(self.context, &self.expr)36	}37}3839#[derive(Trace)]40struct EvaluateNamedLazyVal {41	future_context: FutureWrapper<Context>,42	name: IStr,43	value: LocExpr,44}45impl LazyValValue for EvaluateNamedLazyVal {46	fn get(self: Box<Self>) -> Result<Val> {47		evaluate_named(self.future_context.unwrap(), &self.value, self.name)48	}49}5051pub trait ArgLike {52	fn evaluate_arg(&self, ctx: Context, tailstrict: bool) -> Result<LazyVal>;53}54impl ArgLike for &LocExpr {55	fn evaluate_arg(&self, ctx: Context, tailstrict: bool) -> Result<LazyVal> {56		Ok(if tailstrict {57			LazyVal::new_resolved(evaluate(ctx, self)?)58		} else {59			LazyVal::new(TraceBox(Box::new(EvaluateLazyVal {60				context: ctx,61				expr: (*self).clone(),62			})))63		})64	}65}66impl<T> ArgLike for T67where68	T: Typed + Clone,69	Val: TryFrom<T, Error = LocError>,70{71	fn evaluate_arg(&self, _ctx: Context, _tailstrict: bool) -> Result<LazyVal> {72		let val: Val = Val::try_from(self.clone())?;73		Ok(LazyVal::new_resolved(val))74	}75}76pub enum TlaArg {77	String(IStr),78	Code(LocExpr),79	Val(Val),80}81impl ArgLike for TlaArg {82	fn evaluate_arg(&self, ctx: Context, tailstrict: bool) -> Result<LazyVal> {83		match self {84			TlaArg::String(s) => Ok(LazyVal::new_resolved(Val::Str(s.clone()))),85			TlaArg::Code(code) => Ok(if tailstrict {86				LazyVal::new_resolved(evaluate(ctx, code)?)87			} else {88				LazyVal::new(TraceBox(Box::new(EvaluateLazyVal {89					context: ctx,90					expr: code.clone(),91				})))92			}),93			TlaArg::Val(val) => Ok(LazyVal::new_resolved(val.clone())),94		}95	}96}9798pub trait ArgsLike {99	fn unnamed_len(&self) -> usize;100	fn unnamed_iter(101		&self,102		ctx: Context,103		tailstrict: bool,104		handler: &mut dyn FnMut(usize, LazyVal) -> Result<()>,105	) -> Result<()>;106	fn named_iter(107		&self,108		ctx: Context,109		tailstrict: bool,110		handler: &mut dyn FnMut(&IStr, LazyVal) -> Result<()>,111	) -> Result<()>;112	fn named_names(&self, handler: &mut dyn FnMut(&IStr));113}114115impl ArgsLike for ArgsDesc {116	fn unnamed_len(&self) -> usize {117		self.unnamed.len()118	}119120	fn unnamed_iter(121		&self,122		ctx: Context,123		tailstrict: bool,124		handler: &mut dyn FnMut(usize, LazyVal) -> Result<()>,125	) -> Result<()> {126		for (id, arg) in self.unnamed.iter().enumerate() {127			handler(128				id,129				if tailstrict {130					LazyVal::new_resolved(evaluate(ctx.clone(), arg)?)131				} else {132					LazyVal::new(TraceBox(Box::new(EvaluateLazyVal {133						context: ctx.clone(),134						expr: arg.clone(),135					})))136				},137			)?;138		}139		Ok(())140	}141142	fn named_iter(143		&self,144		ctx: Context,145		tailstrict: bool,146		handler: &mut dyn FnMut(&IStr, LazyVal) -> Result<()>,147	) -> Result<()> {148		for (name, arg) in self.named.iter() {149			handler(150				name,151				if tailstrict {152					LazyVal::new_resolved(evaluate(ctx.clone(), arg)?)153				} else {154					LazyVal::new(TraceBox(Box::new(EvaluateLazyVal {155						context: ctx.clone(),156						expr: arg.clone(),157					})))158				},159			)?;160		}161		Ok(())162	}163164	fn named_names(&self, handler: &mut dyn FnMut(&IStr)) {165		for (name, _) in self.named.iter() {166			handler(name)167		}168	}169}170171impl<A: ArgLike> ArgsLike for [(IStr, A)] {172	fn unnamed_len(&self) -> usize {173		0174	}175176	fn unnamed_iter(177		&self,178		_ctx: Context,179		_tailstrict: bool,180		_handler: &mut dyn FnMut(usize, LazyVal) -> Result<()>,181	) -> Result<()> {182		Ok(())183	}184185	fn named_iter(186		&self,187		ctx: Context,188		tailstrict: bool,189		handler: &mut dyn FnMut(&IStr, LazyVal) -> Result<()>,190	) -> Result<()> {191		for (name, val) in self.iter() {192			handler(name, val.evaluate_arg(ctx.clone(), tailstrict)?)?;193		}194		Ok(())195	}196197	fn named_names(&self, handler: &mut dyn FnMut(&IStr)) {198		for (name, _) in self.iter() {199			handler(name);200		}201	}202}203204impl<A: ArgLike> ArgsLike for HashMap<IStr, A> {205	fn unnamed_len(&self) -> usize {206		0207	}208209	fn unnamed_iter(210		&self,211		_ctx: Context,212		_tailstrict: bool,213		_handler: &mut dyn FnMut(usize, LazyVal) -> Result<()>,214	) -> Result<()> {215		Ok(())216	}217218	fn named_iter(219		&self,220		ctx: Context,221		tailstrict: bool,222		handler: &mut dyn FnMut(&IStr, LazyVal) -> Result<()>,223	) -> Result<()> {224		for (name, value) in self.iter() {225			handler(name, value.evaluate_arg(ctx.clone(), tailstrict)?)?;226		}227		Ok(())228	}229230	fn named_names(&self, handler: &mut dyn FnMut(&IStr)) {231		for (name, _) in self.iter() {232			handler(name);233		}234	}235}236237impl<A: ArgLike> ArgsLike for [A] {238	fn unnamed_len(&self) -> usize {239		self.len()240	}241242	fn unnamed_iter(243		&self,244		ctx: Context,245		tailstrict: bool,246		handler: &mut dyn FnMut(usize, LazyVal) -> Result<()>,247	) -> Result<()> {248		for (i, arg) in self.iter().enumerate() {249			handler(i, arg.evaluate_arg(ctx.clone(), tailstrict)?)?;250		}251		Ok(())252	}253254	fn named_iter(255		&self,256		_ctx: Context,257		_tailstrict: bool,258		_handler: &mut dyn FnMut(&IStr, LazyVal) -> Result<()>,259	) -> Result<()> {260		Ok(())261	}262263	fn named_names(&self, _handler: &mut dyn FnMut(&IStr)) {}264}265impl<A: ArgLike> ArgsLike for &[A] {266	fn unnamed_len(&self) -> usize {267		(*self).unnamed_len()268	}269270	fn unnamed_iter(271		&self,272		ctx: Context,273		tailstrict: bool,274		handler: &mut dyn FnMut(usize, LazyVal) -> Result<()>,275	) -> Result<()> {276		(*self).unnamed_iter(ctx, tailstrict, handler)277	}278279	fn named_iter(280		&self,281		ctx: Context,282		tailstrict: bool,283		handler: &mut dyn FnMut(&IStr, LazyVal) -> Result<()>,284	) -> Result<()> {285		(*self).named_iter(ctx, tailstrict, handler)286	}287288	fn named_names(&self, handler: &mut dyn FnMut(&IStr)) {289		(*self).named_names(handler)290	}291}292293/// Creates correct [context](Context) for function body evaluation returning error on invalid call.294///295/// ## Parameters296/// * `ctx`: used for passed argument expressions' execution and for body execution (if `body_ctx` is not set)297/// * `body_ctx`: used for default parameter values' execution and for body execution (if set)298/// * `params`: function parameters' definition299/// * `args`: passed function arguments300/// * `tailstrict`: if set to `true` function arguments are eagerly executed, otherwise - lazily301pub fn parse_function_call(302	ctx: Context,303	body_ctx: Context,304	params: &ParamsDesc,305	args: &dyn ArgsLike,306	tailstrict: bool,307) -> Result<Context> {308	let mut passed_args = GcHashMap::with_capacity(params.len());309	if args.unnamed_len() > params.len() {310		throw!(TooManyArgsFunctionHas(params.len()))311	}312313	let mut filled_args = 0;314315	args.unnamed_iter(ctx.clone(), tailstrict, &mut |id, arg| {316		let name = params[id].0.clone();317		passed_args.insert(name, arg);318		filled_args += 1;319		Ok(())320	})?;321322	args.named_iter(ctx, tailstrict, &mut |name, value| {323		// FIXME: O(n) for arg existence check324		if !params.iter().any(|p| &p.0 == name) {325			throw!(UnknownFunctionParameter((name as &str).to_owned()));326		}327		if passed_args.insert(name.clone(), value).is_some() {328			throw!(BindingParameterASecondTime(name.clone()));329		}330		filled_args += 1;331		Ok(())332	})?;333334	if filled_args < params.len() {335		// Some args are unset, but maybe we have defaults for them336		// Default values should be created in newly created context337		let future_context = Context::new_future();338		let mut defaults = GcHashMap::with_capacity(params.len() - filled_args);339340		for param in params.iter().filter(|p| p.1.is_some()) {341			if passed_args.contains_key(&param.0.clone()) {342				continue;343			}344			LazyVal::new(TraceBox(Box::new(EvaluateNamedLazyVal {345				future_context: future_context.clone(),346				name: param.0.clone(),347				value: param.1.clone().unwrap(),348			})));349350			defaults.insert(351				param.0.clone(),352				LazyVal::new(TraceBox(Box::new(EvaluateNamedLazyVal {353					future_context: future_context.clone(),354					name: param.0.clone(),355					value: param.1.clone().unwrap(),356				}))),357			);358			filled_args += 1;359		}360361		// Some args still wasn't filled362		if filled_args != params.len() {363			for param in params.iter().skip(args.unnamed_len()) {364				let mut found = false;365				args.named_names(&mut |name| {366					if name == &param.0 {367						found = true;368					}369				});370				if !found {371					throw!(FunctionParameterNotBoundInCall(param.0.clone()));372				}373			}374			unreachable!();375		}376377		Ok(body_ctx378			.extend(passed_args, None, None, None)379			.extend_bound(defaults)380			.into_future(future_context))381	} else {382		let body_ctx = body_ctx.extend(passed_args, None, None, None);383		Ok(body_ctx)384	}385}386387type BuiltinParamName = Cow<'static, str>;388389#[derive(Clone, Trace)]390pub struct BuiltinParam {391	pub name: BuiltinParamName,392	pub has_default: bool,393}394395/// Do not implement it directly, instead use #[builtin] macro396pub trait Builtin: Trace {397	fn name(&self) -> &str;398	fn params(&self) -> &[BuiltinParam];399	fn call(&self, context: Context, loc: CallLocation, args: &dyn ArgsLike) -> Result<Val>;400}401402pub trait StaticBuiltin: Builtin + Send + Sync403where404	Self: 'static,405{406	// In impl, to make it object safe:407	// const INST: &'static Self;408}409410/// You shouldn't probally use this function, use jrsonnet_macros::builtin instead411///412/// ## Parameters413/// * `ctx`: used for passed argument expressions' execution and for body execution (if `body_ctx` is not set)414/// * `params`: function parameters' definition415/// * `args`: passed function arguments416/// * `tailstrict`: if set to `true` function arguments are eagerly executed, otherwise - lazily417pub fn parse_builtin_call(418	ctx: Context,419	params: &[BuiltinParam],420	args: &dyn ArgsLike,421	tailstrict: bool,422) -> Result<GcHashMap<BuiltinParamName, LazyVal>> {423	let mut passed_args = GcHashMap::with_capacity(params.len());424	if args.unnamed_len() > params.len() {425		throw!(TooManyArgsFunctionHas(params.len()))426	}427428	let mut filled_args = 0;429430	args.unnamed_iter(ctx.clone(), tailstrict, &mut |id, arg| {431		let name = params[id].name.clone();432		passed_args.insert(name, arg);433		filled_args += 1;434		Ok(())435	})?;436437	args.named_iter(ctx, tailstrict, &mut |name, arg| {438		// FIXME: O(n) for arg existence check439		let p = params440			.iter()441			.find(|p| p.name == name as &str)442			.ok_or_else(|| UnknownFunctionParameter((name as &str).to_owned()))?;443		if passed_args.insert(p.name.clone(), arg).is_some() {444			throw!(BindingParameterASecondTime(name.clone()));445		}446		filled_args += 1;447		Ok(())448	})?;449450	if filled_args < params.len() {451		for param in params.iter().filter(|p| p.has_default) {452			if passed_args.contains_key(&param.name) {453				continue;454			}455			filled_args += 1;456		}457458		// Some args still wasn't filled459		if filled_args != params.len() {460			for param in params.iter().skip(args.unnamed_len()) {461				let mut found = false;462				args.named_names(&mut |name| {463					if name as &str == &param.name as &str {464						found = true;465					}466				});467				if !found {468					throw!(FunctionParameterNotBoundInCall(param.name.clone().into()));469				}470			}471			unreachable!();472		}473	}474	Ok(passed_args)475}476477/// Creates Context, which has all argument default values applied478/// and with unbound values causing error to be returned479pub fn parse_default_function_call(body_ctx: Context, params: &ParamsDesc) -> Context {480	let ctx = Context::new_future();481482	let mut bindings = GcHashMap::new();483484	#[derive(Trace)]485	struct DependsOnUnbound(IStr);486	impl LazyValValue for DependsOnUnbound {487		fn get(self: Box<Self>) -> Result<Val> {488			Err(FunctionParameterNotBoundInCall(self.0.clone()).into())489		}490	}491492	for param in params.iter() {493		if let Some(v) = &param.1 {494			bindings.insert(495				param.0.clone(),496				LazyVal::new(TraceBox(Box::new(EvaluateNamedLazyVal {497					future_context: ctx.clone(),498					name: param.0.clone(),499					value: v.clone(),500				}))),501			);502		} else {503			bindings.insert(504				param.0.clone(),505				LazyVal::new(TraceBox(Box::new(DependsOnUnbound(param.0.clone())))),506			);507		}508	}509510	body_ctx.extend(bindings, None, None, None).into_future(ctx)511}
modifiedcrates/jrsonnet-evaluator/src/lib.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/lib.rs
+++ b/crates/jrsonnet-evaluator/src/lib.rs
@@ -28,7 +28,7 @@
 pub use dynamic::*;
 use error::{Error::*, LocError, Result, StackTraceElement};
 pub use evaluate::*;
-use function::{Builtin, TlaArg};
+use function::{Builtin, CallLocation, TlaArg};
 use gc::{GcHashMap, TraceBox};
 use gcmodule::{Cc, Trace, Weak};
 pub use import::*;
@@ -173,6 +173,7 @@
 	/// Global state is fine here.
 	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().expect(
@@ -181,7 +182,7 @@
 	})
 }
 pub fn push_frame<T>(
-	e: Option<&ExprLocation>,
+	e: CallLocation,
 	frame_desc: impl FnOnce() -> String,
 	f: impl FnOnce() -> Result<T>,
 ) -> Result<T> {
@@ -345,7 +346,7 @@
 	/// Executes code creating a new stack frame
 	pub fn push<T>(
 		&self,
-		e: Option<&ExprLocation>,
+		e: CallLocation,
 		frame_desc: impl FnOnce() -> String,
 		f: impl FnOnce() -> Result<T>,
 	) -> Result<T> {
@@ -368,7 +369,7 @@
 		}
 		if let Err(mut err) = result {
 			err.trace_mut().0.push(StackTraceElement {
-				location: e.cloned(),
+				location: e.0.cloned(),
 				desc: frame_desc(),
 			});
 			return Err(err);
@@ -512,7 +513,7 @@
 					|| {
 						func.evaluate(
 							self.create_default_context(),
-							None,
+							CallLocation::native(),
 							&self.settings().tla_vars,
 							true,
 						)
modifiedcrates/jrsonnet-evaluator/src/native.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/native.rs
+++ b/crates/jrsonnet-evaluator/src/native.rs
@@ -1,11 +1,10 @@
 #![allow(clippy::type_complexity)]
 
-use crate::function::{parse_builtin_call, ArgsLike, Builtin, BuiltinParam};
+use crate::function::{parse_builtin_call, ArgsLike, Builtin, BuiltinParam, CallLocation};
 use crate::gc::TraceBox;
 use crate::Context;
 use crate::{error::Result, Val};
 use gcmodule::Trace;
-use jrsonnet_parser::ExprLocation;
 use std::path::Path;
 use std::rc::Rc;
 
@@ -32,18 +31,13 @@
 		&self.params
 	}
 
-	fn call(
-		&self,
-		context: Context,
-		loc: Option<&ExprLocation>,
-		args: &dyn ArgsLike,
-	) -> Result<Val> {
+	fn call(&self, context: Context, loc: CallLocation, args: &dyn ArgsLike) -> Result<Val> {
 		let args = parse_builtin_call(context, &self.params, args, true)?;
 		let mut out_args = Vec::with_capacity(self.params.len());
 		for p in self.params.iter() {
 			out_args.push(args[&p.name].evaluate()?);
 		}
-		self.handler.call(loc.map(|l| l.0.clone()), &out_args)
+		self.handler.call(loc.0.map(|l| l.0.clone()), &out_args)
 	}
 }
 
modifiedcrates/jrsonnet-evaluator/src/typed/conversions.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/typed/conversions.rs
+++ b/crates/jrsonnet-evaluator/src/typed/conversions.rs
@@ -1,5 +1,6 @@
 use std::convert::{TryFrom, TryInto};
 
+use gcmodule::Cc;
 use jrsonnet_interner::IStr;
 pub use jrsonnet_macros::Typed;
 use jrsonnet_types::{ComplexValType, ValType};
@@ -8,7 +9,7 @@
 	error::{Error::*, LocError, Result},
 	throw,
 	typed::CheckType,
-	ArrValue, FuncVal, IndexableVal, ObjValue, ObjValueBuilder, Val,
+	ArrValue, FuncDesc, FuncVal, IndexableVal, ObjValue, ObjValueBuilder, Val,
 };
 
 pub trait TypedObj: Typed {
@@ -431,6 +432,30 @@
 		Ok(Self::Func(value))
 	}
 }
+
+impl Typed for Cc<FuncDesc> {
+	const TYPE: &'static ComplexValType = &ComplexValType::Simple(ValType::Func);
+}
+impl TryFrom<Val> for Cc<FuncDesc> {
+	type Error = LocError;
+
+	fn try_from(value: Val) -> Result<Self, Self::Error> {
+		<Self as Typed>::TYPE.check(&value)?;
+		match value {
+			Val::Func(FuncVal::Normal(desc)) => Ok(desc.clone()),
+			Val::Func(_) => throw!(RuntimeError("expected normal function, not builtin".into())),
+			_ => unreachable!(),
+		}
+	}
+}
+impl TryFrom<Cc<FuncDesc>> for Val {
+	type Error = LocError;
+
+	fn try_from(value: Cc<FuncDesc>) -> Result<Self, Self::Error> {
+		Ok(Self::Func(FuncVal::Normal(value)))
+	}
+}
+
 impl Typed for ObjValue {
 	const TYPE: &'static ComplexValType = &ComplexValType::Simple(ValType::Obj);
 }
modifiedcrates/jrsonnet-evaluator/src/val.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/val.rs
+++ b/crates/jrsonnet-evaluator/src/val.rs
@@ -6,14 +6,15 @@
 	error::{Error::*, LocError},
 	evaluate,
 	function::{
-		parse_default_function_call, parse_function_call, ArgsLike, Builtin, StaticBuiltin,
+		parse_default_function_call, parse_function_call, ArgsLike, Builtin, CallLocation,
+		StaticBuiltin,
 	},
 	gc::TraceBox,
 	throw, Context, ObjValue, Result,
 };
 use gcmodule::{Cc, Trace};
 use jrsonnet_interner::IStr;
-use jrsonnet_parser::{ExprLocation, LocExpr, ParamsDesc};
+use jrsonnet_parser::{LocExpr, ParamsDesc};
 use jrsonnet_types::ValType;
 use std::{cell::RefCell, fmt::Debug, rc::Rc};
 
@@ -152,7 +153,7 @@
 	pub fn evaluate(
 		&self,
 		call_ctx: Context,
-		loc: Option<&ExprLocation>,
+		loc: CallLocation,
 		args: &dyn ArgsLike,
 		tailstrict: bool,
 	) -> Result<Val> {
@@ -166,7 +167,7 @@
 		}
 	}
 	pub fn evaluate_simple(&self, args: &dyn ArgsLike) -> Result<Val> {
-		self.evaluate(Context::default(), None, args, true)
+		self.evaluate(Context::default(), CallLocation::native(), args, true)
 	}
 }
 
modifiedcrates/jrsonnet-macros/src/lib.rsdiffbeforeafterboth
--- a/crates/jrsonnet-macros/src/lib.rs
+++ b/crates/jrsonnet-macros/src/lib.rs
@@ -1,5 +1,5 @@
 use proc_macro2::TokenStream;
-use quote::{quote, quote_spanned};
+use quote::quote;
 use syn::{
 	parenthesized,
 	parse::{Parse, ParseStream},
@@ -7,8 +7,8 @@
 	punctuated::Punctuated,
 	spanned::Spanned,
 	token::Comma,
-	Attribute, DeriveInput, Error, FnArg, GenericArgument, Ident, ItemFn, LitStr, Pat, PatType,
-	Path, PathArguments, Result, Token, Type,
+	Attribute, DeriveInput, Error, FnArg, GenericArgument, Ident, ItemFn, LitStr, Pat, Path,
+	PathArguments, Result, ReturnType, Token, Type,
 };
 
 fn parse_attr<A: Parse, I>(attrs: &[Attribute], ident: I) -> Result<Option<A>>
@@ -33,49 +33,42 @@
 	Ok(Some(attr))
 }
 
-fn is_location_arg(t: &PatType) -> bool {
-	t.attrs.iter().any(|a| a.path.is_ident("location"))
-}
-fn is_self_arg(t: &PatType) -> bool {
-	t.attrs.iter().any(|a| a.path.is_ident("self"))
+fn path_is(path: &Path, needed: &str) -> bool {
+	path.leading_colon.is_none()
+		&& path.segments.len() >= 1
+		&& path.segments.iter().last().unwrap().ident == needed
 }
 
-trait RetainHad<T> {
-	fn retain_had(&mut self, h: impl FnMut(&T) -> bool) -> bool;
-}
-impl<T> RetainHad<T> for Vec<T> {
-	fn retain_had(&mut self, h: impl FnMut(&T) -> bool) -> bool {
-		let before = self.len();
-		self.retain(h);
-		let after = self.len();
-		before != after
+fn type_is_path<'ty>(ty: &'ty Type, needed: &str) -> Option<&'ty PathArguments> {
+	match ty {
+		Type::Path(path) if path.qself.is_none() && path_is(&path.path, needed) => {
+			let args = &path.path.segments.iter().last().unwrap().arguments;
+			Some(args)
+		}
+		_ => None,
 	}
 }
 
-fn extract_type_from_option(ty: &Type) -> Option<&Type> {
-	fn path_is_option(path: &Path) -> bool {
-		path.leading_colon.is_none()
-			&& path.segments.len() == 1
-			&& path.segments.iter().next().unwrap().ident == "Option"
-	}
-
-	match ty {
-		Type::Path(typepath) if typepath.qself.is_none() && path_is_option(&typepath.path) => {
-			// Get the first segment of the path (there is only one, in fact: "Option"):
-			let type_params = &typepath.path.segments.iter().next().unwrap().arguments;
-			// It should have only on angle-bracketed param ("<String>"):
-			let generic_arg = match type_params {
-				PathArguments::AngleBracketed(params) => params.args.iter().next().unwrap(),
-				_ => panic!("missing option generic"),
-			};
-			// This argument must be a type:
-			match generic_arg {
-				GenericArgument::Type(ty) => Some(ty),
-				_ => panic!("option generic should be a type"),
+fn extract_type_from_option(ty: &Type) -> Result<Option<&Type>> {
+	Ok(if let Some(args) = type_is_path(ty, "Option") {
+		// It should have only on angle-bracketed param ("<String>"):
+		let generic_arg = match args {
+			PathArguments::AngleBracketed(params) => params.args.iter().next().unwrap(),
+			_ => return Err(Error::new(args.span(), "missing option generic")),
+		};
+		// This argument must be a type:
+		match generic_arg {
+			GenericArgument::Type(ty) => Some(ty),
+			_ => {
+				return Err(Error::new(
+					generic_arg.span(),
+					"option generic should be a type",
+				))
 			}
 		}
-		_ => None,
-	}
+	} else {
+		None
+	})
 }
 
 struct Field {
@@ -101,7 +94,7 @@
 
 struct EmptyAttr;
 impl Parse for EmptyAttr {
-	fn parse(input: ParseStream) -> Result<Self> {
+	fn parse(_input: ParseStream) -> Result<Self> {
 		Ok(Self)
 	}
 }
@@ -124,107 +117,158 @@
 	}
 }
 
+enum ArgInfo {
+	Normal {
+		ty: Type,
+		is_option: bool,
+		name: String,
+		// ident: Ident,
+	},
+	Lazy {
+		is_option: bool,
+		name: String,
+	},
+	Location,
+	This,
+}
+
+impl ArgInfo {
+	fn parse(arg: &FnArg) -> Result<Self> {
+		let typed = match arg {
+			FnArg::Receiver(_) => unreachable!(),
+			FnArg::Typed(a) => a,
+		};
+		let ident = match &typed.pat as &Pat {
+			Pat::Ident(i) => i.ident.clone(),
+			_ => {
+				return Err(Error::new(
+					typed.pat.span(),
+					"arg should be plain identifier",
+				))
+			}
+		};
+		let ty = &typed.ty as &Type;
+		if type_is_path(&ty, "CallLocation").is_some() {
+			return Ok(Self::Location);
+		} else if type_is_path(&ty, "Self").is_some() {
+			return Ok(Self::This);
+		} else if type_is_path(&ty, "LazyVal").is_some() {
+			return Ok(Self::Lazy {
+				is_option: false,
+				name: ident.to_string(),
+			});
+		}
+
+		let (is_option, ty) = if let Some(ty) = extract_type_from_option(&ty)? {
+			if type_is_path(&ty, "LazyVal").is_some() {
+				return Ok(Self::Lazy {
+					is_option: true,
+					name: ident.to_string(),
+				});
+			}
+
+			(true, ty.clone())
+		} else {
+			(false, ty.clone())
+		};
+
+		Ok(Self::Normal {
+			ty,
+			is_option,
+			name: ident.to_string(),
+			// ident,
+		})
+	}
+}
+
 #[proc_macro_attribute]
 pub fn builtin(
 	attr: proc_macro::TokenStream,
 	item: proc_macro::TokenStream,
 ) -> proc_macro::TokenStream {
-	let attrs = parse_macro_input!(attr as BuiltinAttrs);
-	let mut fun: ItemFn = parse_macro_input!(item);
+	let attr = parse_macro_input!(attr as BuiltinAttrs);
+	let item: ItemFn = parse_macro_input!(item);
+
+	match builtin_inner(attr, item) {
+		Ok(v) => v.into(),
+		Err(e) => e.into_compile_error().into(),
+	}
+}
 
+fn builtin_inner(attr: BuiltinAttrs, fun: ItemFn) -> syn::Result<TokenStream> {
 	let result = match fun.sig.output {
-		syn::ReturnType::Default => {
-			return quote_spanned! { fun.sig.span() =>
-				compile_error!("builtins should return something");
-			}
-			.into()
+		ReturnType::Default => {
+			return Err(Error::new(
+				fun.sig.span(),
+				"builtin should return something",
+			))
 		}
-		syn::ReturnType::Type(_, ref ty) => ty.clone(),
+		ReturnType::Type(_, ref ty) => ty.clone(),
 	};
 
-	let params = fun
+	let args = fun
 		.sig
 		.inputs
 		.iter()
-		.map(|i| match i {
-			FnArg::Receiver(_) => unreachable!(),
-			FnArg::Typed(t) => t,
-		})
-		.filter(|a| !is_location_arg(a) && !is_self_arg(a))
-		.map(|t| {
-			let ident = match &t.pat as &Pat {
-				Pat::Ident(i) => i.ident.to_string(),
-				_ => {
-					return quote_spanned! { t.pat.span() =>
-						compile_error!("args should be plain identifiers")
-					}
-					.into()
-				}
-			};
-			let optional = extract_type_from_option(&t.ty).is_some();
-			quote! {
-				BuiltinParam {
-					name: std::borrow::Cow::Borrowed(#ident),
-					has_default: #optional,
-				}
+		.map(|a| ArgInfo::parse(a))
+		.collect::<Result<Vec<_>>>()?;
+
+	let params_desc = args.iter().flat_map(|a| match a {
+		ArgInfo::Normal {
+			is_option, name, ..
+		}
+		| ArgInfo::Lazy { is_option, name } => Some(quote! {
+			BuiltinParam {
+				name: std::borrow::Cow::Borrowed(#name),
+				has_default: #is_option,
 			}
-		})
-		.collect::<Vec<_>>();
+		}),
+		ArgInfo::Location => None,
+		ArgInfo::This => None,
+	});
 
-	let args = fun
-		.sig
-		.inputs
-		.iter_mut()
-		.map(|i| match i {
-			FnArg::Receiver(_) => unreachable!(),
-			FnArg::Typed(t) => t,
-		})
-		.map(|t| {
-			if t.attrs.retain_had(|a| !a.path.is_ident("location")) {
-				quote! {{
-					loc
+	let pass = args.iter().map(|a| match a {
+		ArgInfo::Normal {
+			ty,
+			is_option,
+			name,
+			// ident,
+		} => {
+			let eval = quote! {::jrsonnet_evaluator::push_description_frame(
+				|| format!("argument <{}> evaluation", #name),
+				|| <#ty>::try_from(value.evaluate()?),
+			)?};
+			if *is_option {
+				quote! {if let Some(value) = parsed.get(#name) {
+					Some(#eval)
+				} else {
+					None
 				}}
-			} else if t.attrs.retain_had(|a| !a.path.is_ident("self")) {
+			} else {
 				quote! {{
-					self
+					let value = parsed.get(#name).expect("args shape is checked");
+					#eval
 				}}
-			} else {
-				let ident = match &t.pat as &Pat {
-					Pat::Ident(i) => i.ident.to_string(),
-					_ => {
-						return quote_spanned! { t.pat.span() =>
-							compile_error!("args should be plain identifiers")
-						}
-						.into()
-					}
-				};
-				let ty = &t.ty;
-				if let Some(opt_ty) = extract_type_from_option(&t.ty) {
-					quote! {{
-						if let Some(value) = parsed.get(#ident) {
-							Some(::jrsonnet_evaluator::push_description_frame(
-								|| format!("argument <{}> evaluation", #ident),
-								|| <#opt_ty>::try_from(value.evaluate()?),
-							)?)
-						} else {
-							None
-						}
-					}}
+			}
+		}
+		ArgInfo::Lazy { is_option, name } => {
+			if *is_option {
+				quote! {if let Some(value) = parsed.get(#name) {
+					Some(value.clone())
 				} else {
-					quote! {{
-						let value = parsed.get(#ident).unwrap();
-
-						::jrsonnet_evaluator::push_description_frame(
-							|| format!("argument <{}> evaluation", #ident),
-							|| <#ty>::try_from(value.evaluate()?),
-						)?
-					}}
+					None
+				}}
+			} else {
+				quote! {
+					parsed.get(#name).expect("args shape is correct").clone()
 				}
 			}
-		})
-		.collect::<Vec<_>>();
+		}
+		ArgInfo::Location => quote! {location},
+		ArgInfo::This => quote! {self},
+	});
 
-	let fields = attrs.fields.iter().map(|field| {
+	let fields = attr.fields.iter().map(|field| {
 		let name = &field.name;
 		let ty = &field.ty;
 		quote! {
@@ -234,7 +278,7 @@
 
 	let name = &fun.sig.ident;
 	let vis = &fun.vis;
-	let static_ext = if attrs.fields.is_empty() {
+	let static_ext = if attr.fields.is_empty() {
 		quote! {
 			impl #name {
 				pub const INST: &'static dyn StaticBuiltin = &#name {};
@@ -244,13 +288,13 @@
 	} else {
 		quote! {}
 	};
-	let static_derive_copy = if attrs.fields.is_empty() {
+	let static_derive_copy = if attr.fields.is_empty() {
 		quote! {, Copy}
 	} else {
 		quote! {}
 	};
 
-	(quote! {
+	Ok(quote! {
 		#fun
 		#[doc(hidden)]
 		#[allow(non_camel_case_types)]
@@ -260,12 +304,12 @@
 		}
 		const _: () = {
 			use ::jrsonnet_evaluator::{
-				function::{Builtin, StaticBuiltin, BuiltinParam, ArgsLike, parse_builtin_call},
+				function::{Builtin, CallLocation, StaticBuiltin, BuiltinParam, ArgsLike, parse_builtin_call},
 				error::Result, Context,
 				parser::ExprLocation,
 			};
 			const PARAMS: &'static [BuiltinParam] = &[
-				#(#params),*
+				#(#params_desc),*
 			];
 
 			#static_ext
@@ -279,17 +323,16 @@
 				fn params(&self) -> &[BuiltinParam] {
 					PARAMS
 				}
-				fn call(&self, context: Context, loc: Option<&ExprLocation>, args: &dyn ArgsLike) -> Result<Val> {
+				fn call(&self, context: Context, location: CallLocation, args: &dyn ArgsLike) -> Result<Val> {
 					let parsed = parse_builtin_call(context, &PARAMS, args, false)?;
 
-					let result: #result = #name(#(#args),*);
+					let result: #result = #name(#(#pass),*);
 					let result = result?;
 					result.try_into()
 				}
 			}
 		};
 	})
-	.into()
 }
 
 #[derive(Default)]
@@ -366,15 +409,6 @@
 		)
 	}
 
-	fn expand_shallow_field(&self) -> Option<TokenStream> {
-		if self.is_option() {
-			return None;
-		}
-		let name = self.name()?;
-		Some(quote! {
-			(#name, ComplexValType::Any)
-		})
-	}
 	fn expand_field(&self) -> Option<TokenStream> {
 		if self.is_option() {
 			return None;
@@ -450,7 +484,7 @@
 	}
 
 	fn as_option(&self) -> Option<&Type> {
-		extract_type_from_option(&self.0.ty)
+		extract_type_from_option(&self.0.ty).unwrap()
 	}
 	fn is_option(&self) -> bool {
 		self.as_option().is_some()
@@ -460,25 +494,25 @@
 #[proc_macro_derive(Typed, attributes(typed))]
 pub fn derive_typed(item: proc_macro::TokenStream) -> proc_macro::TokenStream {
 	let input = parse_macro_input!(item as DeriveInput);
+
+	match derive_typed_inner(input) {
+		Ok(v) => v.into(),
+		Err(e) => e.to_compile_error().into(),
+	}
+}
+
+fn derive_typed_inner(input: DeriveInput) -> Result<TokenStream> {
 	let data = match &input.data {
 		syn::Data::Struct(s) => s,
-		_ => {
-			return syn::Error::new(input.span(), "only structs supported")
-				.to_compile_error()
-				.into()
-		}
+		_ => return Err(Error::new(input.span(), "only structs supported")),
 	};
 
 	let ident = &input.ident;
-	let fields = match data
+	let fields = data
 		.fields
 		.iter()
 		.map(TypedField::try_new)
-		.collect::<Result<Vec<_>>>()
-	{
-		Ok(v) => v,
-		Err(e) => return e.to_compile_error().into(),
-	};
+		.collect::<Result<Vec<_>>>()?;
 
 	let typed = {
 		let fields = fields
@@ -499,7 +533,7 @@
 	let fields_parse = fields.iter().map(TypedField::expand_parse);
 	let fields_serialize = fields.iter().map(TypedField::expand_serialize);
 
-	quote! {
+	Ok(quote! {
 		const _: () = {
 			use ::jrsonnet_evaluator::{
 				typed::{ComplexValType, Typed, TypedObj, CheckType},
@@ -540,6 +574,5 @@
 			}
 			()
 		};
-	}
-	.into()
+	})
 }