use std::collections::HashMap; use dhall_syntax::Const::Type; use dhall_syntax::{ BinOp, Builtin, ExprF, InterpolatedText, InterpolatedTextContents, Label, NaiveDouble, }; use crate::core::value::Value; use crate::core::valuef::ValueF; use crate::core::var::{AlphaLabel, Shift, Subst}; use crate::phase::Normalized; // Ad-hoc macro to help construct closures macro_rules! make_closure { (#$var:ident) => { $var.clone() }; (var($var:ident, $n:expr, $($ty:tt)*)) => {{ let var = crate::core::var::AlphaVar::from_var_and_alpha( Label::from(stringify!($var)).into(), $n ); ValueF::Var(var) .into_value_with_type(make_closure!($($ty)*)) }}; // Warning: assumes that $ty, as a dhall value, has type `Type` (λ($var:ident : $($ty:tt)*) -> $($body:tt)*) => {{ let var: AlphaLabel = Label::from(stringify!($var)).into(); let ty = make_closure!($($ty)*); let body = make_closure!($($body)*); let body_ty = body.get_type_not_sort(); let lam_ty = ValueF::Pi(var.clone(), ty.clone(), body_ty) .into_value_with_type(Value::from_const(Type)); ValueF::Lam(var, ty, body).into_value_with_type(lam_ty) }}; (Natural) => { Value::from_builtin(Builtin::Natural) }; (List $($rest:tt)*) => { Value::from_builtin(Builtin::List) .app(make_closure!($($rest)*)) }; (Some($($rest:tt)*)) => {{ let v = make_closure!($($rest)*); let v_type = v.get_type_not_sort(); let opt_v_type = Value::from_builtin(Builtin::Optional).app(v_type); ValueF::NEOptionalLit(v).into_value_with_type(opt_v_type) }}; (1 + $($rest:tt)*) => { ValueF::PartialExpr(ExprF::BinOp( dhall_syntax::BinOp::NaturalPlus, make_closure!($($rest)*), Value::from_valuef_and_type( ValueF::NaturalLit(1), make_closure!(Natural) ), )).into_value_with_type( make_closure!(Natural) ) }; ([ $($head:tt)* ] # $($tail:tt)*) => {{ let head = make_closure!($($head)*); let tail = make_closure!($($tail)*); let list_type = tail.get_type_not_sort(); ValueF::PartialExpr(ExprF::BinOp( dhall_syntax::BinOp::ListAppend, ValueF::NEListLit(vec![head]) .into_value_with_type(list_type.clone()), tail, )).into_value_with_type(list_type) }}; } #[allow(clippy::cognitive_complexity)] pub(crate) fn apply_builtin( b: Builtin, args: Vec, ty: &Value, ) -> ValueF { use dhall_syntax::Builtin::*; use ValueF::*; // Small helper enum enum Ret<'a> { ValueF(ValueF), Value(Value), // For applications that can return a function, it's important to keep the remaining // arguments to apply them to the resulting function. ValueWithRemainingArgs(&'a [Value], Value), DoneAsIs, } let ret = match (b, args.as_slice()) { (OptionalNone, [t]) => Ret::ValueF(EmptyOptionalLit(t.clone())), (NaturalIsZero, [n]) => match &*n.as_whnf() { NaturalLit(n) => Ret::ValueF(BoolLit(*n == 0)), _ => Ret::DoneAsIs, }, (NaturalEven, [n]) => match &*n.as_whnf() { NaturalLit(n) => Ret::ValueF(BoolLit(*n % 2 == 0)), _ => Ret::DoneAsIs, }, (NaturalOdd, [n]) => match &*n.as_whnf() { NaturalLit(n) => Ret::ValueF(BoolLit(*n % 2 != 0)), _ => Ret::DoneAsIs, }, (NaturalToInteger, [n]) => match &*n.as_whnf() { NaturalLit(n) => Ret::ValueF(IntegerLit(*n as isize)), _ => Ret::DoneAsIs, }, (NaturalShow, [n]) => match &*n.as_whnf() { NaturalLit(n) => { Ret::ValueF(TextLit(vec![InterpolatedTextContents::Text( n.to_string(), )])) } _ => Ret::DoneAsIs, }, (NaturalSubtract, [a, b]) => match (&*a.as_whnf(), &*b.as_whnf()) { (NaturalLit(a), NaturalLit(b)) => { Ret::ValueF(NaturalLit(if b > a { b - a } else { 0 })) } (NaturalLit(0), _) => Ret::Value(b.clone()), (_, NaturalLit(0)) => Ret::ValueF(NaturalLit(0)), _ if a == b => Ret::ValueF(NaturalLit(0)), _ => Ret::DoneAsIs, }, (IntegerShow, [n]) => match &*n.as_whnf() { IntegerLit(n) => { let s = if *n < 0 { n.to_string() } else { format!("+{}", n) }; Ret::ValueF(TextLit(vec![InterpolatedTextContents::Text(s)])) } _ => Ret::DoneAsIs, }, (IntegerToDouble, [n]) => match &*n.as_whnf() { IntegerLit(n) => { Ret::ValueF(DoubleLit(NaiveDouble::from(*n as f64))) } _ => Ret::DoneAsIs, }, (DoubleShow, [n]) => match &*n.as_whnf() { DoubleLit(n) => { Ret::ValueF(TextLit(vec![InterpolatedTextContents::Text( n.to_string(), )])) } _ => Ret::DoneAsIs, }, (TextShow, [v]) => match &*v.as_whnf() { TextLit(elts) => { match elts.as_slice() { // Empty string literal. [] => { // Printing InterpolatedText takes care of all the escaping let txt: InterpolatedText = std::iter::empty().collect(); let s = txt.to_string(); Ret::ValueF(TextLit(vec![ InterpolatedTextContents::Text(s), ])) } // If there are no interpolations (invariants ensure that when there are no // interpolations, there is a single Text item) in the literal. [InterpolatedTextContents::Text(s)] => { // Printing InterpolatedText takes care of all the escaping let txt: InterpolatedText = std::iter::once(InterpolatedTextContents::Text( s.clone(), )) .collect(); let s = txt.to_string(); Ret::ValueF(TextLit(vec![ InterpolatedTextContents::Text(s), ])) } _ => Ret::DoneAsIs, } } _ => Ret::DoneAsIs, }, (ListLength, [_, l]) => match &*l.as_whnf() { EmptyListLit(_) => Ret::ValueF(NaturalLit(0)), NEListLit(xs) => Ret::ValueF(NaturalLit(xs.len())), _ => Ret::DoneAsIs, }, (ListHead, [_, l]) => match &*l.as_whnf() { EmptyListLit(n) => Ret::ValueF(EmptyOptionalLit(n.clone())), NEListLit(xs) => { Ret::ValueF(NEOptionalLit(xs.iter().next().unwrap().clone())) } _ => Ret::DoneAsIs, }, (ListLast, [_, l]) => match &*l.as_whnf() { EmptyListLit(n) => Ret::ValueF(EmptyOptionalLit(n.clone())), NEListLit(xs) => Ret::ValueF(NEOptionalLit( xs.iter().rev().next().unwrap().clone(), )), _ => Ret::DoneAsIs, }, (ListReverse, [_, l]) => match &*l.as_whnf() { EmptyListLit(n) => Ret::ValueF(EmptyListLit(n.clone())), NEListLit(xs) => { Ret::ValueF(NEListLit(xs.iter().rev().cloned().collect())) } _ => Ret::DoneAsIs, }, (ListIndexed, [_, l]) => { let l_whnf = l.as_whnf(); match &*l_whnf { EmptyListLit(_) | NEListLit(_) => { // Extract the type of the list elements let t = match &*l_whnf { EmptyListLit(t) => t.clone(), NEListLit(xs) => xs[0].get_type_not_sort(), _ => unreachable!(), }; // Construct the returned record type: { index: Natural, value: t } let mut kts = HashMap::new(); kts.insert("index".into(), Value::from_builtin(Natural)); kts.insert("value".into(), t.clone()); let t = Value::from_valuef_and_type( RecordType(kts), Value::from_const(Type), ); // Construct the new list, with added indices let list = match &*l_whnf { EmptyListLit(_) => EmptyListLit(t), NEListLit(xs) => NEListLit( xs.iter() .enumerate() .map(|(i, e)| { let mut kvs = HashMap::new(); kvs.insert( "index".into(), Value::from_valuef_and_type( NaturalLit(i), Value::from_builtin( Builtin::Natural, ), ), ); kvs.insert("value".into(), e.clone()); Value::from_valuef_and_type( RecordLit(kvs), t.clone(), ) }) .collect(), ), _ => unreachable!(), }; Ret::ValueF(list) } _ => Ret::DoneAsIs, } } (ListBuild, [t, f]) => match &*f.as_whnf() { // fold/build fusion ValueF::AppliedBuiltin(ListFold, args) => { if args.len() >= 2 { Ret::Value(args[1].clone()) } else { // Do we really need to handle this case ? unimplemented!() } } _ => { let list_t = Value::from_builtin(List).app(t.clone()); Ret::Value( f.app(list_t.clone()) .app({ // Move `t` under new variables let t1 = t.under_binder(Label::from("x")); let t2 = t1.under_binder(Label::from("xs")); make_closure!( λ(x : #t) -> λ(xs : List #t1) -> [ var(x, 1, #t2) ] # var(xs, 0, List #t2) ) }) .app( EmptyListLit(t.clone()) .into_value_with_type(list_t), ), ) } }, (ListFold, [_, l, _, cons, nil, r @ ..]) => match &*l.as_whnf() { EmptyListLit(_) => Ret::ValueWithRemainingArgs(r, nil.clone()), NEListLit(xs) => { let mut v = nil.clone(); for x in xs.iter().cloned().rev() { v = cons.app(x).app(v); } Ret::ValueWithRemainingArgs(r, v) } _ => Ret::DoneAsIs, }, (OptionalBuild, [t, f]) => match &*f.as_whnf() { // fold/build fusion ValueF::AppliedBuiltin(OptionalFold, args) => { if args.len() >= 2 { Ret::Value(args[1].clone()) } else { // Do we really need to handle this case ? unimplemented!() } } _ => { let optional_t = Value::from_builtin(Optional).app(t.clone()); Ret::Value( f.app(optional_t.clone()) .app({ let t1 = t.under_binder(Label::from("x")); make_closure!(λ(x: #t) -> Some(var(x, 0, #t1))) }) .app( EmptyOptionalLit(t.clone()) .into_value_with_type(optional_t), ), ) } }, (OptionalFold, [_, v, _, just, nothing, r @ ..]) => match &*v.as_whnf() { EmptyOptionalLit(_) => { Ret::ValueWithRemainingArgs(r, nothing.clone()) } NEOptionalLit(x) => { Ret::ValueWithRemainingArgs(r, just.app(x.clone())) } _ => Ret::DoneAsIs, }, (NaturalBuild, [f]) => match &*f.as_whnf() { // fold/build fusion ValueF::AppliedBuiltin(NaturalFold, args) => { if !args.is_empty() { Ret::Value(args[0].clone()) } else { // Do we really need to handle this case ? unimplemented!() } } _ => Ret::Value( f.app(Value::from_builtin(Natural)) .app(make_closure!( λ(x : Natural) -> 1 + var(x, 0, Natural) )) .app( NaturalLit(0) .into_value_with_type(Value::from_builtin(Natural)), ), ), }, (NaturalFold, [n, t, succ, zero, r @ ..]) => match &*n.as_whnf() { NaturalLit(0) => Ret::ValueWithRemainingArgs(r, zero.clone()), NaturalLit(n) => { let fold = Value::from_builtin(NaturalFold) .app( NaturalLit(n - 1) .into_value_with_type(Value::from_builtin(Natural)), ) .app(t.clone()) .app(succ.clone()) .app(zero.clone()); Ret::ValueWithRemainingArgs(r, succ.app(fold)) } _ => Ret::DoneAsIs, }, _ => Ret::DoneAsIs, }; match ret { Ret::ValueF(v) => v, Ret::Value(v) => v.to_whnf_check_type(ty), Ret::ValueWithRemainingArgs(unconsumed_args, mut v) => { let n_consumed_args = args.len() - unconsumed_args.len(); for x in args.into_iter().skip(n_consumed_args) { v = v.app(x); } v.to_whnf_check_type(ty) } Ret::DoneAsIs => AppliedBuiltin(b, args), } } pub(crate) fn apply_any(f: Value, a: Value, ty: &Value) -> ValueF { let f_borrow = f.as_whnf(); match &*f_borrow { ValueF::Lam(x, _, e) => { e.subst_shift(&x.into(), &a).to_whnf_check_type(ty) } ValueF::AppliedBuiltin(b, args) => { use std::iter::once; let args = args.iter().cloned().chain(once(a.clone())).collect(); apply_builtin(*b, args, ty) } ValueF::UnionConstructor(l, kts) => { ValueF::UnionLit(l.clone(), a, kts.clone()) } _ => { drop(f_borrow); ValueF::PartialExpr(ExprF::App(f, a)) } } } pub(crate) fn squash_textlit( elts: impl Iterator>, ) -> Vec> { use std::mem::replace; use InterpolatedTextContents::{Expr, Text}; fn inner( elts: impl Iterator>, crnt_str: &mut String, ret: &mut Vec>, ) { for contents in elts { match contents { Text(s) => crnt_str.push_str(&s), Expr(e) => { let e_borrow = e.as_whnf(); match &*e_borrow { ValueF::TextLit(elts2) => { inner(elts2.iter().cloned(), crnt_str, ret) } _ => { drop(e_borrow); if !crnt_str.is_empty() { ret.push(Text(replace(crnt_str, String::new()))) } ret.push(Expr(e.clone())) } } } } } } let mut crnt_str = String::new(); let mut ret = Vec::new(); inner(elts, &mut crnt_str, &mut ret); if !crnt_str.is_empty() { ret.push(Text(replace(&mut crnt_str, String::new()))) } ret } pub(crate) fn merge_maps( map1: &HashMap, map2: &HashMap, mut f: F, ) -> Result, Err> where F: FnMut(&K, &V, &V) -> Result, K: std::hash::Hash + Eq + Clone, V: Clone, { let mut kvs = HashMap::new(); for (x, v2) in map2 { let newv = if let Some(v1) = map1.get(x) { f(x, v1, v2)? } else { v2.clone() }; kvs.insert(x.clone(), newv); } for (x, v1) in map1 { // Insert only if key not already present kvs.entry(x.clone()).or_insert_with(|| v1.clone()); } Ok(kvs) } // Small helper enum to avoid repetition enum Ret<'a> { ValueF(ValueF), Value(Value), ValueRef(&'a Value), Expr(ExprF), } fn apply_binop<'a>( o: BinOp, x: &'a Value, y: &'a Value, ty: &Value, ) -> Option> { use BinOp::{ BoolAnd, BoolEQ, BoolNE, BoolOr, Equivalence, ListAppend, NaturalPlus, NaturalTimes, RecursiveRecordMerge, RecursiveRecordTypeMerge, RightBiasedRecordMerge, TextAppend, }; use ValueF::{ BoolLit, EmptyListLit, NEListLit, NaturalLit, RecordLit, RecordType, TextLit, }; let x_borrow = x.as_whnf(); let y_borrow = y.as_whnf(); Some(match (o, &*x_borrow, &*y_borrow) { (BoolAnd, BoolLit(true), _) => Ret::ValueRef(y), (BoolAnd, _, BoolLit(true)) => Ret::ValueRef(x), (BoolAnd, BoolLit(false), _) => Ret::ValueF(BoolLit(false)), (BoolAnd, _, BoolLit(false)) => Ret::ValueF(BoolLit(false)), (BoolAnd, _, _) if x == y => Ret::ValueRef(x), (BoolOr, BoolLit(true), _) => Ret::ValueF(BoolLit(true)), (BoolOr, _, BoolLit(true)) => Ret::ValueF(BoolLit(true)), (BoolOr, BoolLit(false), _) => Ret::ValueRef(y), (BoolOr, _, BoolLit(false)) => Ret::ValueRef(x), (BoolOr, _, _) if x == y => Ret::ValueRef(x), (BoolEQ, BoolLit(true), _) => Ret::ValueRef(y), (BoolEQ, _, BoolLit(true)) => Ret::ValueRef(x), (BoolEQ, BoolLit(x), BoolLit(y)) => Ret::ValueF(BoolLit(x == y)), (BoolEQ, _, _) if x == y => Ret::ValueF(BoolLit(true)), (BoolNE, BoolLit(false), _) => Ret::ValueRef(y), (BoolNE, _, BoolLit(false)) => Ret::ValueRef(x), (BoolNE, BoolLit(x), BoolLit(y)) => Ret::ValueF(BoolLit(x != y)), (BoolNE, _, _) if x == y => Ret::ValueF(BoolLit(false)), (NaturalPlus, NaturalLit(0), _) => Ret::ValueRef(y), (NaturalPlus, _, NaturalLit(0)) => Ret::ValueRef(x), (NaturalPlus, NaturalLit(x), NaturalLit(y)) => { Ret::ValueF(NaturalLit(x + y)) } (NaturalTimes, NaturalLit(0), _) => Ret::ValueF(NaturalLit(0)), (NaturalTimes, _, NaturalLit(0)) => Ret::ValueF(NaturalLit(0)), (NaturalTimes, NaturalLit(1), _) => Ret::ValueRef(y), (NaturalTimes, _, NaturalLit(1)) => Ret::ValueRef(x), (NaturalTimes, NaturalLit(x), NaturalLit(y)) => { Ret::ValueF(NaturalLit(x * y)) } (ListAppend, EmptyListLit(_), _) => Ret::ValueRef(y), (ListAppend, _, EmptyListLit(_)) => Ret::ValueRef(x), (ListAppend, NEListLit(xs), NEListLit(ys)) => Ret::ValueF(NEListLit( xs.iter().chain(ys.iter()).cloned().collect(), )), (TextAppend, TextLit(x), _) if x.is_empty() => Ret::ValueRef(y), (TextAppend, _, TextLit(y)) if y.is_empty() => Ret::ValueRef(x), (TextAppend, TextLit(x), TextLit(y)) => Ret::ValueF(TextLit( squash_textlit(x.iter().chain(y.iter()).cloned()), )), (TextAppend, TextLit(x), _) => { use std::iter::once; let y = InterpolatedTextContents::Expr(y.clone()); Ret::ValueF(TextLit(squash_textlit( x.iter().cloned().chain(once(y)), ))) } (TextAppend, _, TextLit(y)) => { use std::iter::once; let x = InterpolatedTextContents::Expr(x.clone()); Ret::ValueF(TextLit(squash_textlit( once(x).chain(y.iter().cloned()), ))) } (RightBiasedRecordMerge, _, RecordLit(kvs)) if kvs.is_empty() => { Ret::ValueRef(x) } (RightBiasedRecordMerge, RecordLit(kvs), _) if kvs.is_empty() => { Ret::ValueRef(y) } (RightBiasedRecordMerge, RecordLit(kvs1), RecordLit(kvs2)) => { let mut kvs = kvs2.clone(); for (x, v) in kvs1 { // Insert only if key not already present kvs.entry(x.clone()).or_insert_with(|| v.clone()); } Ret::ValueF(RecordLit(kvs)) } (RecursiveRecordMerge, _, RecordLit(kvs)) if kvs.is_empty() => { Ret::ValueRef(x) } (RecursiveRecordMerge, RecordLit(kvs), _) if kvs.is_empty() => { Ret::ValueRef(y) } (RecursiveRecordMerge, RecordLit(kvs1), RecordLit(kvs2)) => { let ty_borrow = ty.as_whnf(); let kts = match &*ty_borrow { RecordType(kts) => kts, _ => unreachable!("Internal type error"), }; let kvs = merge_maps::<_, _, _, !>(kvs1, kvs2, |k, v1, v2| { Ok(Value::from_valuef_and_type( ValueF::PartialExpr(ExprF::BinOp( RecursiveRecordMerge, v1.clone(), v2.clone(), )), kts.get(k).expect("Internal type error").clone(), )) })?; Ret::ValueF(RecordLit(kvs)) } (RecursiveRecordTypeMerge, _, _) | (Equivalence, _, _) => { unreachable!("This case should have been handled in typecheck") } _ => return None, }) } pub(crate) fn normalize_one_layer( expr: ExprF, ty: &Value, ) -> ValueF { use ValueF::{ AppliedBuiltin, BoolLit, DoubleLit, EmptyListLit, IntegerLit, NEListLit, NEOptionalLit, NaturalLit, RecordLit, TextLit, UnionConstructor, UnionLit, UnionType, }; let ret = match expr { ExprF::Import(_) => unreachable!( "There should remain no imports in a resolved expression" ), // Those cases have already been completely handled in the typechecking phase (using // `RetWhole`), so they won't appear here. ExprF::Lam(_, _, _) | ExprF::Pi(_, _, _) | ExprF::Let(_, _, _, _) | ExprF::Embed(_) | ExprF::Const(_) | ExprF::Builtin(_) | ExprF::Var(_) | ExprF::Annot(_, _) | ExprF::RecordType(_) | ExprF::UnionType(_) => { unreachable!("This case should have been handled in typecheck") } ExprF::Assert(_) => Ret::Expr(expr), ExprF::App(v, a) => Ret::Value(v.app(a)), ExprF::BoolLit(b) => Ret::ValueF(BoolLit(b)), ExprF::NaturalLit(n) => Ret::ValueF(NaturalLit(n)), ExprF::IntegerLit(n) => Ret::ValueF(IntegerLit(n)), ExprF::DoubleLit(n) => Ret::ValueF(DoubleLit(n)), ExprF::SomeLit(e) => Ret::ValueF(NEOptionalLit(e)), ExprF::EmptyListLit(ref t) => { // Check if the type is of the form `List x` let t_borrow = t.as_whnf(); match &*t_borrow { AppliedBuiltin(Builtin::List, args) if args.len() == 1 => { Ret::ValueF(EmptyListLit(args[0].clone())) } _ => { drop(t_borrow); Ret::Expr(expr) } } } ExprF::NEListLit(elts) => { Ret::ValueF(NEListLit(elts.into_iter().collect())) } ExprF::RecordLit(kvs) => { Ret::ValueF(RecordLit(kvs.into_iter().collect())) } ExprF::TextLit(elts) => { use InterpolatedTextContents::Expr; let elts: Vec<_> = squash_textlit(elts.into_iter()); // Simplify bare interpolation if let [Expr(th)] = elts.as_slice() { Ret::Value(th.clone()) } else { Ret::ValueF(TextLit(elts)) } } ExprF::BoolIf(ref b, ref e1, ref e2) => { let b_borrow = b.as_whnf(); match &*b_borrow { BoolLit(true) => Ret::ValueRef(e1), BoolLit(false) => Ret::ValueRef(e2), _ => { let e1_borrow = e1.as_whnf(); let e2_borrow = e2.as_whnf(); match (&*e1_borrow, &*e2_borrow) { // Simplify `if b then True else False` (BoolLit(true), BoolLit(false)) => Ret::ValueRef(b), _ if e1 == e2 => Ret::ValueRef(e1), _ => { drop(b_borrow); drop(e1_borrow); drop(e2_borrow); Ret::Expr(expr) } } } } } ExprF::BinOp(o, ref x, ref y) => match apply_binop(o, x, y, ty) { Some(ret) => ret, None => Ret::Expr(expr), }, ExprF::Projection(_, ref ls) if ls.is_empty() => { Ret::ValueF(RecordLit(HashMap::new())) } ExprF::Projection(ref v, ref ls) => { let v_borrow = v.as_whnf(); match &*v_borrow { RecordLit(kvs) => Ret::ValueF(RecordLit( ls.iter() .filter_map(|l| { kvs.get(l).map(|x| (l.clone(), x.clone())) }) .collect(), )), _ => { drop(v_borrow); Ret::Expr(expr) } } } ExprF::Field(ref v, ref l) => { let v_borrow = v.as_whnf(); match &*v_borrow { RecordLit(kvs) => match kvs.get(l) { Some(r) => Ret::Value(r.clone()), None => { drop(v_borrow); Ret::Expr(expr) } }, UnionType(kts) => { Ret::ValueF(UnionConstructor(l.clone(), kts.clone())) } _ => { drop(v_borrow); Ret::Expr(expr) } } } ExprF::ProjectionByExpr(_, _) => { unimplemented!("selection by expression") } ExprF::Merge(ref handlers, ref variant, _) => { let handlers_borrow = handlers.as_whnf(); let variant_borrow = variant.as_whnf(); match (&*handlers_borrow, &*variant_borrow) { (RecordLit(kvs), UnionConstructor(l, _)) => match kvs.get(l) { Some(h) => Ret::Value(h.clone()), None => { drop(handlers_borrow); drop(variant_borrow); Ret::Expr(expr) } }, (RecordLit(kvs), UnionLit(l, v, _)) => match kvs.get(l) { Some(h) => Ret::Value(h.app(v.clone())), None => { drop(handlers_borrow); drop(variant_borrow); Ret::Expr(expr) } }, _ => { drop(handlers_borrow); drop(variant_borrow); Ret::Expr(expr) } } } ExprF::ToMap(_, _) => unimplemented!("toMap"), }; match ret { Ret::ValueF(v) => v, Ret::Value(v) => v.to_whnf_check_type(ty), Ret::ValueRef(v) => v.to_whnf_check_type(ty), Ret::Expr(expr) => ValueF::PartialExpr(expr), } } /// Normalize a ValueF into WHNF pub(crate) fn normalize_whnf(v: ValueF, ty: &Value) -> ValueF { match v { ValueF::AppliedBuiltin(b, args) => apply_builtin(b, args, ty), ValueF::PartialExpr(e) => normalize_one_layer(e, ty), ValueF::TextLit(elts) => { ValueF::TextLit(squash_textlit(elts.into_iter())) } // All other cases are already in WHNF v => v, } }