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-rw-r--r--dhall/src/normalize.rs305
1 files changed, 152 insertions, 153 deletions
diff --git a/dhall/src/normalize.rs b/dhall/src/normalize.rs
index 71e8de2..192a669 100644
--- a/dhall/src/normalize.rs
+++ b/dhall/src/normalize.rs
@@ -38,159 +38,158 @@ fn apply_builtin(
let now_to_expr =
|v: &Now| v.clone().normalize().normalize_to_expr().embed_absurd();
- let ret =
- match (b, args) {
- (OptionalNone, [t]) => EmptyOptionalLit(Now::from_whnf(t.clone())),
- (NaturalIsZero, [NaturalLit(n)]) => BoolLit(*n == 0),
- (NaturalEven, [NaturalLit(n)]) => BoolLit(*n % 2 == 0),
- (NaturalOdd, [NaturalLit(n)]) => BoolLit(*n % 2 != 0),
- (NaturalToInteger, [NaturalLit(n)]) => {
- Expr(rc(ExprF::IntegerLit(*n as isize)))
- }
- (NaturalShow, [NaturalLit(n)]) => {
- TextLit(vec![InterpolatedTextContents::Text(n.to_string())])
- }
- (ListLength, [_, EmptyListLit(_)]) => NaturalLit(0),
- (ListLength, [_, NEListLit(xs)]) => NaturalLit(xs.len()),
- (ListHead, [_, EmptyListLit(n)]) => EmptyOptionalLit(n.clone()),
- (ListHead, [_, NEListLit(xs)]) => {
- NEOptionalLit(xs.first().unwrap().clone())
- }
- (ListLast, [_, EmptyListLit(n)]) => EmptyOptionalLit(n.clone()),
- (ListLast, [_, NEListLit(xs)]) => {
- NEOptionalLit(xs.last().unwrap().clone())
- }
- (ListReverse, [_, EmptyListLit(n)]) => EmptyListLit(n.clone()),
- (ListReverse, [_, NEListLit(xs)]) => {
- let xs = xs.iter().cloned().rev().collect();
- NEListLit(xs)
- }
- (ListIndexed, [_, EmptyListLit(t)]) => {
- // TODO: avoid passing through Exprs
- let t = now_to_expr(t);
- EmptyListLit(Now::new(
- ctx,
- dhall::subexpr!({ index : Natural, value : t }),
- ))
- }
- (ListIndexed, [_, NEListLit(xs)]) => {
- let xs = xs
- .iter()
- .cloned()
- .enumerate()
- .map(|(i, e)| {
- let i = NaturalLit(i);
- let mut kvs = BTreeMap::new();
- kvs.insert("index".into(), Now::from_whnf(i));
- kvs.insert("value".into(), e);
- Now::from_whnf(RecordLit(kvs))
- })
- .collect();
- NEListLit(xs)
- }
- // fold/build fusion
- (ListBuild, [_, WHNF::AppliedBuiltin(_, ListFold, args)])
- if args.len() == 2 =>
- {
- args.get(1).unwrap().clone()
- }
- (ListFold, [_, WHNF::AppliedBuiltin(_, ListBuild, args)])
- if args.len() == 2 =>
- {
- args.get(1).unwrap().clone()
- }
- (ListBuild, [a0, g]) => {
- // TODO: avoid passing through Exprs
- let a0 = whnf_to_expr(a0);
- let a1 = shift0(1, &"x".into(), &a0);
- let g = whnf_to_expr(g);
- normalize_whnf(
- ctx,
- dhall::subexpr!(
- g
- (List a0)
- (λ(x : a0) -> λ(xs : List a1) -> [ x ] # xs)
- ([] : List a0)
- ),
- )
- }
- (ListFold, [_, EmptyListLit(_), _, _, nil]) => nil.clone(),
- (ListFold, [_, NEListLit(xs), _, cons, nil]) => {
- // TODO: avoid passing through Exprs
- let nil = whnf_to_expr(nil);
- let cons = whnf_to_expr(cons);
- normalize_whnf(
- ctx,
- xs.iter().rev().fold(nil, |acc, x| {
- let x = now_to_expr(x);
- let acc = acc.clone();
- dhall::subexpr!(cons x acc)
- }),
- )
- }
- // fold/build fusion
- (
- OptionalBuild,
- [_, WHNF::AppliedBuiltin(_, OptionalFold, args)],
- ) if args.len() == 2 => args.get(1).unwrap().clone(),
- (
- OptionalFold,
- [_, WHNF::AppliedBuiltin(_, OptionalBuild, args)],
- ) if args.len() == 2 => args.get(1).unwrap().clone(),
- (OptionalBuild, [a0, g]) => {
- // TODO: avoid passing through Exprs
- let a0 = whnf_to_expr(a0);
- let g = whnf_to_expr(g);
- normalize_whnf(
- ctx,
- dhall::subexpr!(
- g
- (Optional a0)
- (λ(x: a0) -> Some x)
- (None a0)
- ),
- )
- }
- (OptionalFold, [_, EmptyOptionalLit(_), _, _, nothing]) => {
- nothing.clone()
- }
- (OptionalFold, [_, NEOptionalLit(x), _, just, _]) => {
- // TODO: avoid passing through Exprs
- let just = whnf_to_expr(just);
- let x = now_to_expr(x);
- normalize_whnf(ctx, dhall::subexpr!(just x))
- }
- // fold/build fusion
- (NaturalBuild, [WHNF::AppliedBuiltin(_, NaturalFold, args)])
- if args.len() == 1 =>
- {
- args.get(0).unwrap().clone()
- }
- (NaturalFold, [WHNF::AppliedBuiltin(_, NaturalBuild, args)])
- if args.len() == 1 =>
- {
- args.get(0).unwrap().clone()
- }
- (NaturalBuild, [g]) => {
- // TODO: avoid passing through Exprs
- let g = whnf_to_expr(g);
- normalize_whnf(
- ctx,
- dhall::subexpr!(g Natural (λ(x : Natural) -> x + 1) 0),
- )
- }
- (NaturalFold, [NaturalLit(0), _, _, zero]) => zero.clone(),
- (NaturalFold, [NaturalLit(n), t, succ, zero]) => {
- // TODO: avoid passing through Exprs
- let t = whnf_to_expr(t);
- let succ = whnf_to_expr(succ);
- let zero = whnf_to_expr(zero);
- let fold = rc(ExprF::Builtin(NaturalFold));
- let n = rc(ExprF::NaturalLit(n - 1));
- normalize_whnf(ctx, dhall::subexpr!(succ (fold n t succ zero)))
- }
- _ => return None,
- };
+ let ret = match (b, args) {
+ (OptionalNone, [t]) => EmptyOptionalLit(Now::from_whnf(t.clone())),
+ (NaturalIsZero, [NaturalLit(n)]) => BoolLit(*n == 0),
+ (NaturalEven, [NaturalLit(n)]) => BoolLit(*n % 2 == 0),
+ (NaturalOdd, [NaturalLit(n)]) => BoolLit(*n % 2 != 0),
+ (NaturalToInteger, [NaturalLit(n)]) => {
+ Expr(rc(ExprF::IntegerLit(*n as isize)))
+ }
+ (NaturalShow, [NaturalLit(n)]) => {
+ TextLit(vec![InterpolatedTextContents::Text(n.to_string())])
+ }
+ (ListLength, [_, EmptyListLit(_)]) => NaturalLit(0),
+ (ListLength, [_, NEListLit(xs)]) => NaturalLit(xs.len()),
+ (ListHead, [_, EmptyListLit(n)]) => EmptyOptionalLit(n.clone()),
+ (ListHead, [_, NEListLit(xs)]) => {
+ NEOptionalLit(xs.first().unwrap().clone())
+ }
+ (ListLast, [_, EmptyListLit(n)]) => EmptyOptionalLit(n.clone()),
+ (ListLast, [_, NEListLit(xs)]) => {
+ NEOptionalLit(xs.last().unwrap().clone())
+ }
+ (ListReverse, [_, EmptyListLit(n)]) => EmptyListLit(n.clone()),
+ (ListReverse, [_, NEListLit(xs)]) => {
+ let xs = xs.iter().cloned().rev().collect();
+ NEListLit(xs)
+ }
+ (ListIndexed, [_, EmptyListLit(t)]) => {
+ // TODO: avoid passing through Exprs
+ let t = now_to_expr(t);
+ EmptyListLit(Now::new(
+ ctx,
+ dhall::subexpr!({ index : Natural, value : t }),
+ ))
+ }
+ (ListIndexed, [_, NEListLit(xs)]) => {
+ let xs = xs
+ .iter()
+ .cloned()
+ .enumerate()
+ .map(|(i, e)| {
+ let i = NaturalLit(i);
+ let mut kvs = BTreeMap::new();
+ kvs.insert("index".into(), Now::from_whnf(i));
+ kvs.insert("value".into(), e);
+ Now::from_whnf(RecordLit(kvs))
+ })
+ .collect();
+ NEListLit(xs)
+ }
+ // fold/build fusion
+ (ListBuild, [_, WHNF::AppliedBuiltin(_, ListFold, args)])
+ if args.len() == 2 =>
+ {
+ args.get(1).unwrap().clone()
+ }
+ (ListFold, [_, WHNF::AppliedBuiltin(_, ListBuild, args)])
+ if args.len() == 2 =>
+ {
+ args.get(1).unwrap().clone()
+ }
+ (ListBuild, [a0, g]) => {
+ // TODO: avoid passing through Exprs
+ let a0 = whnf_to_expr(a0);
+ let a1 = shift0(1, &"x".into(), &a0);
+ let g = whnf_to_expr(g);
+ normalize_whnf(
+ ctx,
+ dhall::subexpr!(
+ g
+ (List a0)
+ (λ(x : a0) -> λ(xs : List a1) -> [ x ] # xs)
+ ([] : List a0)
+ ),
+ )
+ }
+ (ListFold, [_, EmptyListLit(_), _, _, nil]) => nil.clone(),
+ (ListFold, [_, NEListLit(xs), _, cons, nil]) => {
+ // TODO: avoid passing through Exprs
+ let nil = whnf_to_expr(nil);
+ let cons = whnf_to_expr(cons);
+ normalize_whnf(
+ ctx,
+ xs.iter().rev().fold(nil, |acc, x| {
+ let x = now_to_expr(x);
+ let acc = acc.clone();
+ dhall::subexpr!(cons x acc)
+ }),
+ )
+ }
+ // fold/build fusion
+ (
+ OptionalBuild,
+ [_, WHNF::AppliedBuiltin(_, OptionalFold, args)],
+ ) if args.len() == 2 => args.get(1).unwrap().clone(),
+ (
+ OptionalFold,
+ [_, WHNF::AppliedBuiltin(_, OptionalBuild, args)],
+ ) if args.len() == 2 => args.get(1).unwrap().clone(),
+ (OptionalBuild, [a0, g]) => {
+ // TODO: avoid passing through Exprs
+ let a0 = whnf_to_expr(a0);
+ let g = whnf_to_expr(g);
+ normalize_whnf(
+ ctx,
+ dhall::subexpr!(
+ g
+ (Optional a0)
+ (λ(x: a0) -> Some x)
+ (None a0)
+ ),
+ )
+ }
+ (OptionalFold, [_, EmptyOptionalLit(_), _, _, nothing]) => {
+ nothing.clone()
+ }
+ (OptionalFold, [_, NEOptionalLit(x), _, just, _]) => {
+ // TODO: avoid passing through Exprs
+ let just = whnf_to_expr(just);
+ let x = now_to_expr(x);
+ normalize_whnf(ctx, dhall::subexpr!(just x))
+ }
+ // fold/build fusion
+ (NaturalBuild, [WHNF::AppliedBuiltin(_, NaturalFold, args)])
+ if args.len() == 1 =>
+ {
+ args.get(0).unwrap().clone()
+ }
+ (NaturalFold, [WHNF::AppliedBuiltin(_, NaturalBuild, args)])
+ if args.len() == 1 =>
+ {
+ args.get(0).unwrap().clone()
+ }
+ (NaturalBuild, [g]) => {
+ // TODO: avoid passing through Exprs
+ let g = whnf_to_expr(g);
+ normalize_whnf(
+ ctx,
+ dhall::subexpr!(g Natural (λ(x : Natural) -> x + 1) 0),
+ )
+ }
+ (NaturalFold, [NaturalLit(0), _, _, zero]) => zero.clone(),
+ (NaturalFold, [NaturalLit(n), t, succ, zero]) => {
+ // TODO: avoid passing through Exprs
+ let t = whnf_to_expr(t);
+ let succ = whnf_to_expr(succ);
+ let zero = whnf_to_expr(zero);
+ let fold = rc(ExprF::Builtin(NaturalFold));
+ let n = rc(ExprF::NaturalLit(n - 1));
+ normalize_whnf(ctx, dhall::subexpr!(succ (fold n t succ zero)))
+ }
+ _ => return None,
+ };
Some(ret)
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-23 23:23:09 +0000