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authorNadrieril Feneanar2020-02-19 17:25:57 +0000
committerGitHub2020-02-19 17:25:57 +0000
commitffbde252a850c7d96e1000e1be52792c41733a28 (patch)
treee668b7f764fb4981a802bc619e0b2ff62fa9ce16 /dhall/src/syntax
parente4b3a879907b6dcc75d25847ae21a23d0201aae1 (diff)
parent7cbfc1a0d32766a383d1f48902502adaa2234d2f (diff)
Merge pull request #131 from Nadrieril/hir
Decouple main expression types
Diffstat (limited to '')
-rw-r--r--dhall/src/syntax/ast/expr.rs140
-rw-r--r--dhall/src/syntax/ast/import.rs24
-rw-r--r--dhall/src/syntax/ast/visitor.rs397
-rw-r--r--dhall/src/syntax/binary/decode.rs20
-rw-r--r--dhall/src/syntax/binary/encode.rs53
-rw-r--r--dhall/src/syntax/text/parser.rs21
-rw-r--r--dhall/src/syntax/text/printer.rs47
7 files changed, 194 insertions, 508 deletions
diff --git a/dhall/src/syntax/ast/expr.rs b/dhall/src/syntax/ast/expr.rs
index b493fdb..a479b53 100644
--- a/dhall/src/syntax/ast/expr.rs
+++ b/dhall/src/syntax/ast/expr.rs
@@ -1,5 +1,6 @@
+use crate::semantics::Universe;
use crate::syntax::map::{DupTreeMap, DupTreeSet};
-use crate::syntax::visitor::{self, ExprKindMutVisitor, ExprKindVisitor};
+use crate::syntax::visitor;
use crate::syntax::*;
pub type Integer = isize;
@@ -18,6 +19,12 @@ pub enum Const {
Sort,
}
+impl Const {
+ pub(crate) fn to_universe(self) -> Universe {
+ Universe::from_const(self)
+ }
+}
+
/// Bound variable
///
/// The `Label` field is the variable's name (i.e. \"`x`\").
@@ -96,20 +103,34 @@ pub enum Builtin {
// Each node carries an annotation.
#[derive(Debug, Clone)]
-pub struct Expr<Embed> {
- kind: Box<ExprKind<Expr<Embed>, Embed>>,
+pub struct Expr {
+ kind: Box<ExprKind<Expr>>,
span: Span,
}
-pub type UnspannedExpr<Embed> = ExprKind<Expr<Embed>, Embed>;
+pub type UnspannedExpr = ExprKind<Expr>;
+
+/// Simple literals
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum LitKind {
+ /// `True`
+ Bool(bool),
+ /// `1`
+ Natural(Natural),
+ /// `+2`
+ Integer(Integer),
+ /// `3.24`
+ Double(Double),
+}
/// Syntax tree for expressions
// Having the recursion out of the enum definition enables writing
// much more generic code and improves pattern-matching behind
// smart pointers.
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub enum ExprKind<SubExpr, Embed> {
+pub enum ExprKind<SubExpr> {
Const(Const),
+ Lit(LitKind),
/// `x`
/// `x@n`
Var(V),
@@ -131,16 +152,8 @@ pub enum ExprKind<SubExpr, Embed> {
Builtin(Builtin),
// Binary operations
BinOp(BinOp, SubExpr, SubExpr),
- /// `True`
- BoolLit(bool),
/// `if x then y else z`
BoolIf(SubExpr, SubExpr, SubExpr),
- /// `1`
- NaturalLit(Natural),
- /// `+2`
- IntegerLit(Integer),
- /// `3.24`
- DoubleLit(Double),
/// `"Some ${interpolated} text"`
TextLit(InterpolatedText<SubExpr>),
/// `[] : t`
@@ -169,29 +182,21 @@ pub enum ExprKind<SubExpr, Embed> {
Completion(SubExpr, SubExpr),
/// `./some/path`
Import(Import<SubExpr>),
- /// Embeds the result of resolving an import
- Embed(Embed),
}
-impl<SE, E> ExprKind<SE, E> {
+impl<SE> ExprKind<SE> {
pub fn traverse_ref_maybe_binder<'a, SE2, Err>(
&'a self,
visit: impl FnMut(Option<&'a Label>, &'a SE) -> Result<SE2, Err>,
- ) -> Result<ExprKind<SE2, E>, Err>
- where
- E: Clone,
- {
- visitor::TraverseRefMaybeBinderVisitor(visit).visit(self)
+ ) -> Result<ExprKind<SE2>, Err> {
+ visitor::visit_ref(self, visit)
}
pub fn traverse_ref_with_special_handling_of_binders<'a, SE2, Err>(
&'a self,
mut visit_subexpr: impl FnMut(&'a SE) -> Result<SE2, Err>,
mut visit_under_binder: impl FnMut(&'a Label, &'a SE) -> Result<SE2, Err>,
- ) -> Result<ExprKind<SE2, E>, Err>
- where
- E: Clone,
- {
+ ) -> Result<ExprKind<SE2>, Err> {
self.traverse_ref_maybe_binder(|l, x| match l {
None => visit_subexpr(x),
Some(l) => visit_under_binder(l, x),
@@ -201,27 +206,14 @@ impl<SE, E> ExprKind<SE, E> {
pub(crate) fn traverse_ref<'a, SE2, Err>(
&'a self,
mut visit_subexpr: impl FnMut(&'a SE) -> Result<SE2, Err>,
- ) -> Result<ExprKind<SE2, E>, Err>
- where
- E: Clone,
- {
+ ) -> Result<ExprKind<SE2>, Err> {
self.traverse_ref_maybe_binder(|_, e| visit_subexpr(e))
}
- fn traverse_mut<'a, Err>(
- &'a mut self,
- visit_subexpr: impl FnMut(&'a mut SE) -> Result<(), Err>,
- ) -> Result<(), Err> {
- visitor::TraverseMutVisitor { visit_subexpr }.visit(self)
- }
-
pub fn map_ref_maybe_binder<'a, SE2>(
&'a self,
mut map: impl FnMut(Option<&'a Label>, &'a SE) -> SE2,
- ) -> ExprKind<SE2, E>
- where
- E: Clone,
- {
+ ) -> ExprKind<SE2> {
trivial_result(self.traverse_ref_maybe_binder(|l, x| Ok(map(l, x))))
}
@@ -229,10 +221,7 @@ impl<SE, E> ExprKind<SE, E> {
&'a self,
mut map_subexpr: impl FnMut(&'a SE) -> SE2,
mut map_under_binder: impl FnMut(&'a Label, &'a SE) -> SE2,
- ) -> ExprKind<SE2, E>
- where
- E: Clone,
- {
+ ) -> ExprKind<SE2> {
self.map_ref_maybe_binder(|l, x| match l {
None => map_subexpr(x),
Some(l) => map_under_binder(l, x),
@@ -242,34 +231,30 @@ impl<SE, E> ExprKind<SE, E> {
pub fn map_ref<'a, SE2>(
&'a self,
mut map_subexpr: impl FnMut(&'a SE) -> SE2,
- ) -> ExprKind<SE2, E>
- where
- E: Clone,
- {
+ ) -> ExprKind<SE2> {
self.map_ref_maybe_binder(|_, e| map_subexpr(e))
}
-
- pub fn map_mut<'a>(&'a mut self, mut map_subexpr: impl FnMut(&'a mut SE)) {
- trivial_result(self.traverse_mut(|x| Ok(map_subexpr(x))))
- }
}
-impl<E> Expr<E> {
- pub fn as_ref(&self) -> &UnspannedExpr<E> {
+impl Expr {
+ pub fn as_ref(&self) -> &UnspannedExpr {
+ &self.kind
+ }
+ pub fn kind(&self) -> &UnspannedExpr {
&self.kind
}
pub fn span(&self) -> Span {
self.span.clone()
}
- pub fn new(kind: UnspannedExpr<E>, span: Span) -> Self {
+ pub fn new(kind: UnspannedExpr, span: Span) -> Self {
Expr {
kind: Box::new(kind),
span,
}
}
- pub fn rewrap<E2>(&self, kind: UnspannedExpr<E2>) -> Expr<E2> {
+ pub fn rewrap(&self, kind: UnspannedExpr) -> Expr {
Expr {
kind: Box::new(kind),
span: self.span.clone(),
@@ -281,43 +266,6 @@ impl<E> Expr<E> {
span,
}
}
-
- pub fn traverse_resolve_mut<Err, F1>(
- &mut self,
- f: &mut F1,
- ) -> Result<(), Err>
- where
- E: Clone,
- F1: FnMut(Import<Expr<E>>) -> Result<E, Err>,
- {
- match self.kind.as_mut() {
- ExprKind::BinOp(BinOp::ImportAlt, l, r) => {
- let garbage_expr = ExprKind::BoolLit(false);
- let new_self = if l.traverse_resolve_mut(f).is_ok() {
- l
- } else {
- r.traverse_resolve_mut(f)?;
- r
- };
- *self.kind =
- std::mem::replace(new_self.kind.as_mut(), garbage_expr);
- }
- _ => {
- self.kind.traverse_mut(|e| e.traverse_resolve_mut(f))?;
- if let ExprKind::Import(import) = self.kind.as_mut() {
- let garbage_import = Import {
- mode: ImportMode::Code,
- location: ImportLocation::Missing,
- hash: None,
- };
- // Move out of &mut import
- let import = std::mem::replace(import, garbage_import);
- *self.kind = ExprKind::Embed(f(import)?);
- }
- }
- }
- Ok(())
- }
}
pub fn trivial_result<T>(x: Result<T, !>) -> T {
@@ -362,15 +310,15 @@ impl From<Label> for V {
}
}
-impl<Embed: PartialEq> std::cmp::PartialEq for Expr<Embed> {
+impl std::cmp::PartialEq for Expr {
fn eq(&self, other: &Self) -> bool {
self.kind == other.kind
}
}
-impl<Embed: Eq> std::cmp::Eq for Expr<Embed> {}
+impl std::cmp::Eq for Expr {}
-impl<Embed: std::hash::Hash> std::hash::Hash for Expr<Embed> {
+impl std::hash::Hash for Expr {
fn hash<H>(&self, state: &mut H)
where
H: std::hash::Hasher,
diff --git a/dhall/src/syntax/ast/import.rs b/dhall/src/syntax/ast/import.rs
index da3e99b..7bde6e0 100644
--- a/dhall/src/syntax/ast/import.rs
+++ b/dhall/src/syntax/ast/import.rs
@@ -75,15 +75,6 @@ impl<SE> URL<SE> {
headers,
})
}
- pub fn traverse_mut<'a, Err>(
- &'a mut self,
- f: impl FnOnce(&'a mut SE) -> Result<(), Err>,
- ) -> Result<(), Err> {
- if let Some(header) = &mut self.headers {
- f(header)?;
- }
- Ok(())
- }
}
impl<SE> ImportLocation<SE> {
@@ -99,15 +90,6 @@ impl<SE> ImportLocation<SE> {
Missing => Missing,
})
}
- pub fn traverse_mut<'a, Err>(
- &'a mut self,
- f: impl FnOnce(&'a mut SE) -> Result<(), Err>,
- ) -> Result<(), Err> {
- if let ImportLocation::Remote(url) = self {
- url.traverse_mut(f)?;
- }
- Ok(())
- }
}
impl<SE> Import<SE> {
@@ -121,10 +103,4 @@ impl<SE> Import<SE> {
hash: self.hash.clone(),
})
}
- pub fn traverse_mut<'a, Err>(
- &'a mut self,
- f: impl FnOnce(&'a mut SE) -> Result<(), Err>,
- ) -> Result<(), Err> {
- self.location.traverse_mut(f)
- }
}
diff --git a/dhall/src/syntax/ast/visitor.rs b/dhall/src/syntax/ast/visitor.rs
index 6a1ce7d..c361bc1 100644
--- a/dhall/src/syntax/ast/visitor.rs
+++ b/dhall/src/syntax/ast/visitor.rs
@@ -2,343 +2,112 @@ use std::iter::FromIterator;
use crate::syntax::*;
-/// A visitor trait that can be used to traverse `ExprKind`s. We need this pattern so that Rust lets
-/// us have as much mutability as we can.
-/// For example, `traverse_ref_with_special_handling_of_binders` cannot be made using only
-/// `traverse_ref`, because `traverse_ref` takes a `FnMut` so we would need to pass multiple
-/// mutable reverences to this argument to `traverse_ref`. But Rust's ownership system is all about
-/// preventing exactly this ! So we have to be more clever. The visitor pattern allows us to have
-/// only one mutable thing the whole time: the visitor itself. The visitor can then carry around
-/// multiple closures or just one, and Rust is ok with either. See for example TraverseRefVisitor.
-pub trait ExprKindVisitor<'a, SE1, SE2, E1, E2>: Sized {
- type Error;
-
- fn visit_subexpr(&mut self, subexpr: &'a SE1) -> Result<SE2, Self::Error>;
- fn visit_embed(self, embed: &'a E1) -> Result<E2, Self::Error>;
-
- fn visit_subexpr_under_binder(
- mut self,
- _label: &'a Label,
- subexpr: &'a SE1,
- ) -> Result<SE2, Self::Error> {
- self.visit_subexpr(subexpr)
- }
-
- fn visit(
- self,
- input: &'a ExprKind<SE1, E1>,
- ) -> Result<ExprKind<SE2, E2>, Self::Error> {
- visit_ref(self, input)
- }
+fn vec<'a, T, U, Err>(
+ x: &'a [T],
+ f: impl FnMut(&'a T) -> Result<U, Err>,
+) -> Result<Vec<U>, Err> {
+ x.iter().map(f).collect()
}
-/// Like `ExprKindVisitor`, but by mutable reference
-pub trait ExprKindMutVisitor<'a, SE, E>: Sized {
- type Error;
-
- fn visit_subexpr(&mut self, subexpr: &'a mut SE)
- -> Result<(), Self::Error>;
- fn visit_embed(self, _embed: &'a mut E) -> Result<(), Self::Error> {
- Ok(())
- }
-
- fn visit_subexpr_under_binder(
- mut self,
- _label: &'a mut Label,
- subexpr: &'a mut SE,
- ) -> Result<(), Self::Error> {
- self.visit_subexpr(subexpr)
- }
+fn opt<'a, T, U, Err>(
+ x: &'a Option<T>,
+ f: impl FnOnce(&'a T) -> Result<U, Err>,
+) -> Result<Option<U>, Err> {
+ Ok(match x {
+ Some(x) => Some(f(x)?),
+ None => None,
+ })
+}
- fn visit(self, input: &'a mut ExprKind<SE, E>) -> Result<(), Self::Error> {
- visit_mut(self, input)
- }
+fn dupmap<'a, SE1, SE2, T, Err>(
+ x: impl IntoIterator<Item = (&'a Label, &'a SE1)>,
+ mut f: impl FnMut(&'a SE1) -> Result<SE2, Err>,
+) -> Result<T, Err>
+where
+ SE1: 'a,
+ T: FromIterator<(Label, SE2)>,
+{
+ x.into_iter().map(|(k, x)| Ok((k.clone(), f(x)?))).collect()
}
-fn visit_ref<'a, V, SE1, SE2, E1, E2>(
- mut v: V,
- input: &'a ExprKind<SE1, E1>,
-) -> Result<ExprKind<SE2, E2>, V::Error>
+fn optdupmap<'a, SE1, SE2, T, Err>(
+ x: impl IntoIterator<Item = (&'a Label, &'a Option<SE1>)>,
+ mut f: impl FnMut(&'a SE1) -> Result<SE2, Err>,
+) -> Result<T, Err>
where
- V: ExprKindVisitor<'a, SE1, SE2, E1, E2>,
+ SE1: 'a,
+ T: FromIterator<(Label, Option<SE2>)>,
{
- fn vec<'a, T, U, Err, F: FnMut(&'a T) -> Result<U, Err>>(
- x: &'a [T],
- f: F,
- ) -> Result<Vec<U>, Err> {
- x.iter().map(f).collect()
- }
- fn opt<'a, T, U, Err, F: FnOnce(&'a T) -> Result<U, Err>>(
- x: &'a Option<T>,
- f: F,
- ) -> Result<Option<U>, Err> {
- Ok(match x {
- Some(x) => Some(f(x)?),
- None => None,
+ x.into_iter()
+ .map(|(k, x)| {
+ Ok((
+ k.clone(),
+ match x {
+ Some(x) => Some(f(x)?),
+ None => None,
+ },
+ ))
})
- }
- fn dupmap<'a, V, SE1, SE2, E1, E2, T>(
- x: impl IntoIterator<Item = (&'a Label, &'a SE1)>,
- mut v: V,
- ) -> Result<T, V::Error>
- where
- SE1: 'a,
- T: FromIterator<(Label, SE2)>,
- V: ExprKindVisitor<'a, SE1, SE2, E1, E2>,
- {
- x.into_iter()
- .map(|(k, x)| Ok((k.clone(), v.visit_subexpr(x)?)))
- .collect()
- }
- fn optdupmap<'a, V, SE1, SE2, E1, E2, T>(
- x: impl IntoIterator<Item = (&'a Label, &'a Option<SE1>)>,
- mut v: V,
- ) -> Result<T, V::Error>
- where
- SE1: 'a,
- T: FromIterator<(Label, Option<SE2>)>,
- V: ExprKindVisitor<'a, SE1, SE2, E1, E2>,
- {
- x.into_iter()
- .map(|(k, x)| {
- Ok((
- k.clone(),
- match x {
- Some(x) => Some(v.visit_subexpr(x)?),
- None => None,
- },
- ))
- })
- .collect()
+ .collect()
+}
+
+pub(crate) fn visit_ref<'a, F, SE1, SE2, Err>(
+ input: &'a ExprKind<SE1>,
+ mut f: F,
+) -> Result<ExprKind<SE2>, Err>
+where
+ F: FnMut(Option<&'a Label>, &'a SE1) -> Result<SE2, Err>,
+{
+ // Can't use closures because of borrowing rules
+ macro_rules! expr {
+ ($e:expr) => {
+ f(None, $e)
+ };
+ ($l:expr, $e:expr) => {
+ f(Some($l), $e)
+ };
}
use crate::syntax::ExprKind::*;
Ok(match input {
Var(v) => Var(v.clone()),
Lam(l, t, e) => {
- let t = v.visit_subexpr(t)?;
- let e = v.visit_subexpr_under_binder(l, e)?;
+ let t = expr!(t)?;
+ let e = expr!(l, e)?;
Lam(l.clone(), t, e)
}
Pi(l, t, e) => {
- let t = v.visit_subexpr(t)?;
- let e = v.visit_subexpr_under_binder(l, e)?;
+ let t = expr!(t)?;
+ let e = expr!(l, e)?;
Pi(l.clone(), t, e)
}
Let(l, t, a, e) => {
- let t = opt(t, &mut |e| v.visit_subexpr(e))?;
- let a = v.visit_subexpr(a)?;
- let e = v.visit_subexpr_under_binder(l, e)?;
+ let t = opt(t, &mut |e| expr!(e))?;
+ let a = expr!(a)?;
+ let e = expr!(l, e)?;
Let(l.clone(), t, a, e)
}
- App(f, a) => App(v.visit_subexpr(f)?, v.visit_subexpr(a)?),
- Annot(x, t) => Annot(v.visit_subexpr(x)?, v.visit_subexpr(t)?),
+ App(f, a) => App(expr!(f)?, expr!(a)?),
+ Annot(x, t) => Annot(expr!(x)?, expr!(t)?),
Const(k) => Const(*k),
Builtin(v) => Builtin(*v),
- BoolLit(b) => BoolLit(*b),
- NaturalLit(n) => NaturalLit(*n),
- IntegerLit(n) => IntegerLit(*n),
- DoubleLit(n) => DoubleLit(*n),
- TextLit(t) => TextLit(t.traverse_ref(|e| v.visit_subexpr(e))?),
- BinOp(o, x, y) => BinOp(*o, v.visit_subexpr(x)?, v.visit_subexpr(y)?),
- BoolIf(b, t, f) => BoolIf(
- v.visit_subexpr(b)?,
- v.visit_subexpr(t)?,
- v.visit_subexpr(f)?,
- ),
- EmptyListLit(t) => EmptyListLit(v.visit_subexpr(t)?),
- NEListLit(es) => NEListLit(vec(es, |e| v.visit_subexpr(e))?),
- SomeLit(e) => SomeLit(v.visit_subexpr(e)?),
- RecordType(kts) => RecordType(dupmap(kts, v)?),
- RecordLit(kvs) => RecordLit(dupmap(kvs, v)?),
- UnionType(kts) => UnionType(optdupmap(kts, v)?),
- Merge(x, y, t) => Merge(
- v.visit_subexpr(x)?,
- v.visit_subexpr(y)?,
- opt(t, |e| v.visit_subexpr(e))?,
- ),
- ToMap(x, t) => {
- ToMap(v.visit_subexpr(x)?, opt(t, |e| v.visit_subexpr(e))?)
- }
- Field(e, l) => Field(v.visit_subexpr(e)?, l.clone()),
- Projection(e, ls) => Projection(v.visit_subexpr(e)?, ls.clone()),
- ProjectionByExpr(e, x) => {
- ProjectionByExpr(v.visit_subexpr(e)?, v.visit_subexpr(x)?)
- }
- Completion(e, x) => {
- Completion(v.visit_subexpr(e)?, v.visit_subexpr(x)?)
- }
- Assert(e) => Assert(v.visit_subexpr(e)?),
- Import(i) => Import(i.traverse_ref(|e| v.visit_subexpr(e))?),
- Embed(a) => Embed(v.visit_embed(a)?),
+ Lit(l) => Lit(l.clone()),
+ TextLit(t) => TextLit(t.traverse_ref(|e| expr!(e))?),
+ BinOp(o, x, y) => BinOp(*o, expr!(x)?, expr!(y)?),
+ BoolIf(b, t, f) => BoolIf(expr!(b)?, expr!(t)?, expr!(f)?),
+ EmptyListLit(t) => EmptyListLit(expr!(t)?),
+ NEListLit(es) => NEListLit(vec(es, |e| expr!(e))?),
+ SomeLit(e) => SomeLit(expr!(e)?),
+ RecordType(kts) => RecordType(dupmap(kts, |e| expr!(e))?),
+ RecordLit(kvs) => RecordLit(dupmap(kvs, |e| expr!(e))?),
+ UnionType(kts) => UnionType(optdupmap(kts, |e| expr!(e))?),
+ Merge(x, y, t) => Merge(expr!(x)?, expr!(y)?, opt(t, |e| expr!(e))?),
+ ToMap(x, t) => ToMap(expr!(x)?, opt(t, |e| expr!(e))?),
+ Field(e, l) => Field(expr!(e)?, l.clone()),
+ Projection(e, ls) => Projection(expr!(e)?, ls.clone()),
+ ProjectionByExpr(e, x) => ProjectionByExpr(expr!(e)?, expr!(x)?),
+ Completion(e, x) => Completion(expr!(e)?, expr!(x)?),
+ Assert(e) => Assert(expr!(e)?),
+ Import(i) => Import(i.traverse_ref(|e| expr!(e))?),
})
}
-
-fn visit_mut<'a, V, SE, E>(
- mut v: V,
- input: &'a mut ExprKind<SE, E>,
-) -> Result<(), V::Error>
-where
- V: ExprKindMutVisitor<'a, SE, E>,
-{
- fn vec<'a, V, SE, E>(v: &mut V, x: &'a mut Vec<SE>) -> Result<(), V::Error>
- where
- V: ExprKindMutVisitor<'a, SE, E>,
- {
- for x in x {
- v.visit_subexpr(x)?;
- }
- Ok(())
- }
- fn opt<'a, V, SE, E>(
- v: &mut V,
- x: &'a mut Option<SE>,
- ) -> Result<(), V::Error>
- where
- V: ExprKindMutVisitor<'a, SE, E>,
- {
- if let Some(x) = x {
- v.visit_subexpr(x)?;
- }
- Ok(())
- }
- fn dupmap<'a, V, SE, E>(
- mut v: V,
- x: impl IntoIterator<Item = (&'a Label, &'a mut SE)>,
- ) -> Result<(), V::Error>
- where
- SE: 'a,
- V: ExprKindMutVisitor<'a, SE, E>,
- {
- for (_, x) in x {
- v.visit_subexpr(x)?;
- }
- Ok(())
- }
- fn optdupmap<'a, V, SE, E>(
- mut v: V,
- x: impl IntoIterator<Item = (&'a Label, &'a mut Option<SE>)>,
- ) -> Result<(), V::Error>
- where
- SE: 'a,
- V: ExprKindMutVisitor<'a, SE, E>,
- {
- for (_, x) in x {
- opt(&mut v, x)?;
- }
- Ok(())
- }
-
- use crate::syntax::ExprKind::*;
- match input {
- Var(_) | Const(_) | Builtin(_) | BoolLit(_) | NaturalLit(_)
- | IntegerLit(_) | DoubleLit(_) => {}
- Lam(l, t, e) => {
- v.visit_subexpr(t)?;
- v.visit_subexpr_under_binder(l, e)?;
- }
- Pi(l, t, e) => {
- v.visit_subexpr(t)?;
- v.visit_subexpr_under_binder(l, e)?;
- }
- Let(l, t, a, e) => {
- opt(&mut v, t)?;
- v.visit_subexpr(a)?;
- v.visit_subexpr_under_binder(l, e)?;
- }
- App(f, a) => {
- v.visit_subexpr(f)?;
- v.visit_subexpr(a)?;
- }
- Annot(x, t) => {
- v.visit_subexpr(x)?;
- v.visit_subexpr(t)?;
- }
- TextLit(t) => t.traverse_mut(|e| v.visit_subexpr(e))?,
- BinOp(_, x, y) => {
- v.visit_subexpr(x)?;
- v.visit_subexpr(y)?;
- }
- BoolIf(b, t, f) => {
- v.visit_subexpr(b)?;
- v.visit_subexpr(t)?;
- v.visit_subexpr(f)?;
- }
- EmptyListLit(t) => v.visit_subexpr(t)?,
- NEListLit(es) => vec(&mut v, es)?,
- SomeLit(e) => v.visit_subexpr(e)?,
- RecordType(kts) => dupmap(v, kts)?,
- RecordLit(kvs) => dupmap(v, kvs)?,
- UnionType(kts) => optdupmap(v, kts)?,
- Merge(x, y, t) => {
- v.visit_subexpr(x)?;
- v.visit_subexpr(y)?;
- opt(&mut v, t)?;
- }
- ToMap(x, t) => {
- v.visit_subexpr(x)?;
- opt(&mut v, t)?;
- }
- Field(e, _) => v.visit_subexpr(e)?,
- Projection(e, _) => v.visit_subexpr(e)?,
- ProjectionByExpr(e, x) => {
- v.visit_subexpr(e)?;
- v.visit_subexpr(x)?;
- }
- Completion(x, y) => {
- v.visit_subexpr(x)?;
- v.visit_subexpr(y)?;
- }
- Assert(e) => v.visit_subexpr(e)?,
- Import(i) => i.traverse_mut(|e| v.visit_subexpr(e))?,
- Embed(a) => v.visit_embed(a)?,
- }
- Ok(())
-}
-
-pub struct TraverseRefMaybeBinderVisitor<F>(pub F);
-
-impl<'a, SE, E, SE2, Err, F> ExprKindVisitor<'a, SE, SE2, E, E>
- for TraverseRefMaybeBinderVisitor<F>
-where
- SE: 'a,
- E: 'a + Clone,
- F: FnMut(Option<&'a Label>, &'a SE) -> Result<SE2, Err>,
-{
- type Error = Err;
-
- fn visit_subexpr(&mut self, subexpr: &'a SE) -> Result<SE2, Self::Error> {
- (self.0)(None, subexpr)
- }
- fn visit_subexpr_under_binder(
- mut self,
- label: &'a Label,
- subexpr: &'a SE,
- ) -> Result<SE2, Self::Error> {
- (self.0)(Some(label), subexpr)
- }
- fn visit_embed(self, embed: &'a E) -> Result<E, Self::Error> {
- Ok(embed.clone())
- }
-}
-
-pub struct TraverseMutVisitor<F1> {
- pub visit_subexpr: F1,
-}
-
-impl<'a, SE, E, Err, F1> ExprKindMutVisitor<'a, SE, E>
- for TraverseMutVisitor<F1>
-where
- SE: 'a,
- E: 'a,
- F1: FnMut(&'a mut SE) -> Result<(), Err>,
-{
- type Error = Err;
-
- fn visit_subexpr(
- &mut self,
- subexpr: &'a mut SE,
- ) -> Result<(), Self::Error> {
- (self.visit_subexpr)(subexpr)
- }
-}
diff --git a/dhall/src/syntax/binary/decode.rs b/dhall/src/syntax/binary/decode.rs
index 52b699c..2e50d61 100644
--- a/dhall/src/syntax/binary/decode.rs
+++ b/dhall/src/syntax/binary/decode.rs
@@ -6,8 +6,8 @@ use crate::error::DecodeError;
use crate::syntax;
use crate::syntax::{
Expr, ExprKind, FilePath, FilePrefix, Hash, ImportLocation, ImportMode,
- Integer, InterpolatedText, Label, Natural, Scheme, Span, UnspannedExpr,
- URL, V,
+ Integer, InterpolatedText, Label, LitKind, Natural, Scheme, Span,
+ UnspannedExpr, URL, V,
};
use crate::DecodedExpr;
@@ -19,7 +19,7 @@ pub(crate) fn decode(data: &[u8]) -> Result<DecodedExpr, DecodeError> {
}
// Should probably rename this
-fn rc<E>(x: UnspannedExpr<E>) -> Expr<E> {
+fn rc(x: UnspannedExpr) -> Expr {
Expr::new(x, Span::Decoded)
}
@@ -31,8 +31,8 @@ fn cbor_value_to_dhall(data: &cbor::Value) -> Result<DecodedExpr, DecodeError> {
String(s) => match Builtin::parse(s) {
Some(b) => ExprKind::Builtin(b),
None => match s.as_str() {
- "True" => BoolLit(true),
- "False" => BoolLit(false),
+ "True" => Lit(LitKind::Bool(true)),
+ "False" => Lit(LitKind::Bool(false)),
"Type" => Const(Const::Type),
"Kind" => Const(Const::Kind),
"Sort" => Const(Const::Sort),
@@ -40,8 +40,8 @@ fn cbor_value_to_dhall(data: &cbor::Value) -> Result<DecodedExpr, DecodeError> {
},
},
U64(n) => Var(V(Label::from("_"), *n as usize)),
- F64(x) => DoubleLit((*x).into()),
- Bool(b) => BoolLit(*b),
+ F64(x) => Lit(LitKind::Double((*x).into())),
+ Bool(b) => Lit(LitKind::Bool(*b)),
Array(vec) => match vec.as_slice() {
[String(l), U64(n)] => {
if l.as_str() == "_" {
@@ -216,9 +216,9 @@ fn cbor_value_to_dhall(data: &cbor::Value) -> Result<DecodedExpr, DecodeError> {
let z = cbor_value_to_dhall(&z)?;
BoolIf(x, y, z)
}
- [U64(15), U64(x)] => NaturalLit(*x as Natural),
- [U64(16), U64(x)] => IntegerLit(*x as Integer),
- [U64(16), I64(x)] => IntegerLit(*x as Integer),
+ [U64(15), U64(x)] => Lit(LitKind::Natural(*x as Natural)),
+ [U64(16), U64(x)] => Lit(LitKind::Integer(*x as Integer)),
+ [U64(16), I64(x)] => Lit(LitKind::Integer(*x as Integer)),
[U64(18), String(first), rest @ ..] => {
TextLit(InterpolatedText::from((
first.clone(),
diff --git a/dhall/src/syntax/binary/encode.rs b/dhall/src/syntax/binary/encode.rs
index 5e79f2d..291ac4a 100644
--- a/dhall/src/syntax/binary/encode.rs
+++ b/dhall/src/syntax/binary/encode.rs
@@ -9,17 +9,16 @@ use crate::syntax::{
Label, Scheme, V,
};
-/// Warning: will fail if `expr` contains an `Embed` node.
-pub(crate) fn encode<E>(expr: &Expr<E>) -> Result<Vec<u8>, EncodeError> {
+pub(crate) fn encode(expr: &Expr) -> Result<Vec<u8>, EncodeError> {
serde_cbor::ser::to_vec(&Serialize::Expr(expr))
.map_err(|e| EncodeError::CBORError(e))
}
-enum Serialize<'a, E> {
- Expr(&'a Expr<E>),
+enum Serialize<'a> {
+ Expr(&'a Expr),
CBOR(cbor::Value),
- RecordMap(&'a DupTreeMap<Label, Expr<E>>),
- UnionMap(&'a DupTreeMap<Label, Option<Expr<E>>>),
+ RecordMap(&'a DupTreeMap<Label, Expr>),
+ UnionMap(&'a DupTreeMap<Label, Option<Expr>>),
}
macro_rules! count {
@@ -39,7 +38,7 @@ macro_rules! ser_seq {
}};
}
-fn serialize_subexpr<S, E>(ser: S, e: &Expr<E>) -> Result<S::Ok, S::Error>
+fn serialize_subexpr<S>(ser: S, e: &Expr) -> Result<S::Ok, S::Error>
where
S: serde::ser::Serializer,
{
@@ -47,13 +46,14 @@ where
use std::iter::once;
use syntax::Builtin;
use syntax::ExprKind::*;
+ use syntax::LitKind::*;
use self::Serialize::{RecordMap, UnionMap};
- fn expr<E>(x: &Expr<E>) -> self::Serialize<'_, E> {
+ fn expr(x: &Expr) -> self::Serialize<'_> {
self::Serialize::Expr(x)
}
let cbor =
- |v: cbor::Value| -> self::Serialize<'_, E> { self::Serialize::CBOR(v) };
+ |v: cbor::Value| -> self::Serialize<'_> { self::Serialize::CBOR(v) };
let tag = |x: u64| cbor(U64(x));
let null = || cbor(cbor::Value::Null);
let label = |l: &Label| cbor(cbor::Value::String(l.into()));
@@ -61,10 +61,10 @@ where
match e.as_ref() {
Const(c) => ser.serialize_str(&c.to_string()),
Builtin(b) => ser.serialize_str(&b.to_string()),
- BoolLit(b) => ser.serialize_bool(*b),
- NaturalLit(n) => ser_seq!(ser; tag(15), U64(*n as u64)),
- IntegerLit(n) => ser_seq!(ser; tag(16), I64(*n as i64)),
- DoubleLit(n) => {
+ Lit(Bool(b)) => ser.serialize_bool(*b),
+ Lit(Natural(n)) => ser_seq!(ser; tag(15), U64(*n as u64)),
+ Lit(Integer(n)) => ser_seq!(ser; tag(16), I64(*n as i64)),
+ Lit(Double(n)) => {
let n: f64 = (*n).into();
ser.serialize_f64(n)
}
@@ -166,16 +166,10 @@ where
}
Completion(x, y) => ser_seq!(ser; tag(3), tag(13), expr(x), expr(y)),
Import(import) => serialize_import(ser, import),
- Embed(_) => unimplemented!(
- "An expression with resolved imports cannot be binary-encoded"
- ),
}
}
-fn serialize_import<S, E>(
- ser: S,
- import: &Import<Expr<E>>,
-) -> Result<S::Ok, S::Error>
+fn serialize_import<S>(ser: S, import: &Import<Expr>) -> Result<S::Ok, S::Error>
where
S: serde::ser::Serializer,
{
@@ -256,7 +250,7 @@ where
ser_seq.end()
}
-impl<'a, E> serde::ser::Serialize for Serialize<'a, E> {
+impl<'a> serde::ser::Serialize for Serialize<'a> {
fn serialize<S>(&self, ser: S) -> Result<S::Ok, S::Error>
where
S: serde::ser::Serializer,
@@ -282,10 +276,8 @@ impl<'a, E> serde::ser::Serialize for Serialize<'a, E> {
}
}
-fn collect_nested_applications<'a, E>(
- e: &'a Expr<E>,
-) -> (&'a Expr<E>, Vec<&'a Expr<E>>) {
- fn go<'a, E>(e: &'a Expr<E>, vec: &mut Vec<&'a Expr<E>>) -> &'a Expr<E> {
+fn collect_nested_applications<'a>(e: &'a Expr) -> (&'a Expr, Vec<&'a Expr>) {
+ fn go<'a>(e: &'a Expr, vec: &mut Vec<&'a Expr>) -> &'a Expr {
match e.as_ref() {
ExprKind::App(f, a) => {
vec.push(a);
@@ -299,15 +291,10 @@ fn collect_nested_applications<'a, E>(
(e, vec)
}
-type LetBinding<'a, E> = (&'a Label, &'a Option<Expr<E>>, &'a Expr<E>);
+type LetBinding<'a> = (&'a Label, &'a Option<Expr>, &'a Expr);
-fn collect_nested_lets<'a, E>(
- e: &'a Expr<E>,
-) -> (&'a Expr<E>, Vec<LetBinding<'a, E>>) {
- fn go<'a, E>(
- e: &'a Expr<E>,
- vec: &mut Vec<LetBinding<'a, E>>,
- ) -> &'a Expr<E> {
+fn collect_nested_lets<'a>(e: &'a Expr) -> (&'a Expr, Vec<LetBinding<'a>>) {
+ fn go<'a>(e: &'a Expr, vec: &mut Vec<LetBinding<'a>>) -> &'a Expr {
match e.as_ref() {
ExprKind::Let(l, t, v, e) => {
vec.push((l, t, v));
diff --git a/dhall/src/syntax/text/parser.rs b/dhall/src/syntax/text/parser.rs
index 8d571c0..f3ebd2b 100644
--- a/dhall/src/syntax/text/parser.rs
+++ b/dhall/src/syntax/text/parser.rs
@@ -5,23 +5,20 @@ use std::rc::Rc;
use pest_consume::{match_nodes, Parser};
-use crate::syntax;
use crate::syntax::map::{DupTreeMap, DupTreeSet};
use crate::syntax::ExprKind::*;
+use crate::syntax::LitKind::*;
use crate::syntax::{
- Double, FilePath, FilePrefix, Hash, ImportLocation, ImportMode, Integer,
- InterpolatedText, InterpolatedTextContents, Label, NaiveDouble, Natural,
- Scheme, Span, URL, V,
+ Double, Expr, FilePath, FilePrefix, Hash, ImportLocation, ImportMode,
+ Integer, InterpolatedText, InterpolatedTextContents, Label, NaiveDouble,
+ Natural, Scheme, Span, UnspannedExpr, URL, V,
};
-use crate::Normalized;
// This file consumes the parse tree generated by pest and turns it into
// our own AST. All those custom macros should eventually moved into
// their own crate because they are quite general and useful. For now they
// are here and hopefully you can figure out how they work.
-type Expr = syntax::Expr<Normalized>;
-type UnspannedExpr = syntax::UnspannedExpr<Normalized>;
type ParsedText = InterpolatedText<Expr>;
type ParsedTextContents = InterpolatedTextContents<Expr>;
type ParseInput<'input> = pest_consume::Node<'input, Rule, Rc<str>>;
@@ -348,8 +345,8 @@ impl DhallParser {
let e = match crate::syntax::Builtin::parse(s) {
Some(b) => Builtin(b),
None => match s {
- "True" => BoolLit(true),
- "False" => BoolLit(false),
+ "True" => Lit(Bool(true)),
+ "False" => Lit(Bool(false)),
"Type" => Const(crate::syntax::Const::Type),
"Kind" => Const(crate::syntax::Const::Kind),
"Sort" => Const(crate::syntax::Const::Sort),
@@ -837,9 +834,9 @@ impl DhallParser {
#[alias(expression, shortcut = true)]
fn primitive_expression(input: ParseInput) -> ParseResult<Expr> {
Ok(match_nodes!(input.children();
- [double_literal(n)] => spanned(input, DoubleLit(n)),
- [natural_literal(n)] => spanned(input, NaturalLit(n)),
- [integer_literal(n)] => spanned(input, IntegerLit(n)),
+ [double_literal(n)] => spanned(input, Lit(Double(n))),
+ [natural_literal(n)] => spanned(input, Lit(Natural(n))),
+ [integer_literal(n)] => spanned(input, Lit(Integer(n))),
[double_quote_literal(s)] => spanned(input, TextLit(s)),
[single_quote_literal(s)] => spanned(input, TextLit(s)),
[record_type_or_literal(e)] => spanned(input, e),
diff --git a/dhall/src/syntax/text/printer.rs b/dhall/src/syntax/text/printer.rs
index 06dd70f..8891d41 100644
--- a/dhall/src/syntax/text/printer.rs
+++ b/dhall/src/syntax/text/printer.rs
@@ -19,17 +19,17 @@ enum PrintPhase {
// Wraps an Expr with a phase, so that phase selection can be done separate from the actual
// printing.
#[derive(Clone)]
-struct PhasedExpr<'a, E>(&'a Expr<E>, PrintPhase);
+struct PhasedExpr<'a>(&'a Expr, PrintPhase);
-impl<'a, E: Display + Clone> PhasedExpr<'a, E> {
- fn phase(self, phase: PrintPhase) -> PhasedExpr<'a, E> {
+impl<'a> PhasedExpr<'a> {
+ fn phase(self, phase: PrintPhase) -> PhasedExpr<'a> {
PhasedExpr(self.0, phase)
}
}
-impl<E: Display + Clone> UnspannedExpr<E> {
+impl UnspannedExpr {
// Annotate subexpressions with the appropriate phase, defaulting to Base
- fn annotate_with_phases<'a>(&'a self) -> ExprKind<PhasedExpr<'a, E>, E> {
+ fn annotate_with_phases<'a>(&'a self) -> ExprKind<PhasedExpr<'a>> {
use crate::syntax::ExprKind::*;
use PrintPhase::*;
let with_base = self.map_ref(|e| PhasedExpr(e, Base));
@@ -134,7 +134,7 @@ where
}
/// Generic instance that delegates to subexpressions
-impl<SE: Display + Clone, E: Display> Display for ExprKind<SE, E> {
+impl<SE: Display + Clone> Display for ExprKind<SE> {
fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
use crate::syntax::ExprKind::*;
match self {
@@ -196,15 +196,7 @@ impl<SE: Display + Clone, E: Display> Display for ExprKind<SE, E> {
Var(a) => a.fmt(f)?,
Const(k) => k.fmt(f)?,
Builtin(v) => v.fmt(f)?,
- BoolLit(true) => f.write_str("True")?,
- BoolLit(false) => f.write_str("False")?,
- NaturalLit(a) => a.fmt(f)?,
- IntegerLit(a) if *a >= 0 => {
- f.write_str("+")?;
- a.fmt(f)?;
- }
- IntegerLit(a) => a.fmt(f)?,
- DoubleLit(a) => a.fmt(f)?,
+ Lit(a) => a.fmt(f)?,
TextLit(a) => a.fmt(f)?,
RecordType(a) if a.is_empty() => f.write_str("{}")?,
RecordType(a) => fmt_list("{ ", ", ", " }", a, f, |(k, t), f| {
@@ -232,19 +224,36 @@ impl<SE: Display + Clone, E: Display> Display for ExprKind<SE, E> {
write!(f, "{}::{}", a, b)?;
}
Import(a) => a.fmt(f)?,
- Embed(a) => a.fmt(f)?,
}
Ok(())
}
}
-impl<E: Display + Clone> Display for Expr<E> {
+impl Display for Expr {
+ fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+ self.kind().fmt_phase(f, PrintPhase::Base)
+ }
+}
+
+impl Display for LitKind {
fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
- self.as_ref().fmt_phase(f, PrintPhase::Base)
+ use LitKind::*;
+ match self {
+ Bool(true) => f.write_str("True")?,
+ Bool(false) => f.write_str("False")?,
+ Natural(a) => a.fmt(f)?,
+ Integer(a) if *a >= 0 => {
+ f.write_str("+")?;
+ a.fmt(f)?;
+ }
+ Integer(a) => a.fmt(f)?,
+ Double(a) => a.fmt(f)?,
+ }
+ Ok(())
}
}
-impl<'a, E: Display + Clone> Display for PhasedExpr<'a, E> {
+impl<'a> Display for PhasedExpr<'a> {
fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
self.0.as_ref().fmt_phase(f, self.1)
}