diff options
Diffstat (limited to 'dhall_core/src/core.rs')
| -rw-r--r-- | dhall_core/src/core.rs | 170 |
1 files changed, 64 insertions, 106 deletions
diff --git a/dhall_core/src/core.rs b/dhall_core/src/core.rs index 7eaf08e..89fb6b9 100644 --- a/dhall_core/src/core.rs +++ b/dhall_core/src/core.rs @@ -1,7 +1,6 @@ #![allow(non_snake_case)] use std::collections::BTreeMap; use std::fmt::{self, Display}; -use std::hash::Hash; use std::path::PathBuf; /// Constants for a pure type system @@ -139,8 +138,8 @@ impl Label { /// Zero indices are omitted when pretty-printing `Var`s and non-zero indices /// appear as a numeric suffix. /// -#[derive(Debug, Copy, Clone, PartialEq, Eq)] -pub struct V<Label>(pub Label, pub usize); +#[derive(Debug, Clone, PartialEq, Eq)] +pub struct V(pub Label, pub usize); #[derive(Debug, Copy, Clone, PartialEq, Eq)] pub enum BinOp { @@ -172,52 +171,40 @@ pub enum BinOp { /// Syntax tree for expressions #[derive(Debug, Clone, PartialEq)] -pub enum Expr<Label, Note, Embed> { +pub enum Expr<Note, Embed> { /// `Const c ~ c` Const(Const), /// `Var (V x 0) ~ x`<br> /// `Var (V x n) ~ x@n` - Var(V<Label>), + Var(V), /// `Lam x A b ~ λ(x : A) -> b` - Lam( - Label, - Box<Expr<Label, Note, Embed>>, - Box<Expr<Label, Note, Embed>>, - ), + Lam(Label, Box<Expr<Note, Embed>>, Box<Expr<Note, Embed>>), /// `Pi "_" A B ~ A -> B` /// `Pi x A B ~ ∀(x : A) -> B` - Pi( - Label, - Box<Expr<Label, Note, Embed>>, - Box<Expr<Label, Note, Embed>>, - ), + Pi(Label, Box<Expr<Note, Embed>>, Box<Expr<Note, Embed>>), /// `App f A ~ f A` - App(Box<Expr<Label, Note, Embed>>, Box<Expr<Label, Note, Embed>>), + App(Box<Expr<Note, Embed>>, Box<Expr<Note, Embed>>), /// `Let x Nothing r e ~ let x = r in e` /// `Let x (Just t) r e ~ let x : t = r in e` Let( Label, - Option<Box<Expr<Label, Note, Embed>>>, - Box<Expr<Label, Note, Embed>>, - Box<Expr<Label, Note, Embed>>, + Option<Box<Expr<Note, Embed>>>, + Box<Expr<Note, Embed>>, + Box<Expr<Note, Embed>>, ), /// `Annot x t ~ x : t` - Annot(Box<Expr<Label, Note, Embed>>, Box<Expr<Label, Note, Embed>>), + Annot(Box<Expr<Note, Embed>>, Box<Expr<Note, Embed>>), /// Built-in values Builtin(Builtin), // Binary operations - BinOp( - BinOp, - Box<Expr<Label, Note, Embed>>, - Box<Expr<Label, Note, Embed>>, - ), + BinOp(BinOp, Box<Expr<Note, Embed>>, Box<Expr<Note, Embed>>), /// `BoolLit b ~ b` BoolLit(bool), /// `BoolIf x y z ~ if x then y else z` BoolIf( - Box<Expr<Label, Note, Embed>>, - Box<Expr<Label, Note, Embed>>, - Box<Expr<Label, Note, Embed>>, + Box<Expr<Note, Embed>>, + Box<Expr<Note, Embed>>, + Box<Expr<Note, Embed>>, ), /// `NaturalLit n ~ +n` NaturalLit(Natural), @@ -228,38 +215,32 @@ pub enum Expr<Label, Note, Embed> { /// `TextLit t ~ t` TextLit(Builder), /// `ListLit t [x, y, z] ~ [x, y, z] : List t` - ListLit( - Option<Box<Expr<Label, Note, Embed>>>, - Vec<Expr<Label, Note, Embed>>, - ), + ListLit(Option<Box<Expr<Note, Embed>>>, Vec<Expr<Note, Embed>>), /// `OptionalLit t [e] ~ [e] : Optional t` /// `OptionalLit t [] ~ [] : Optional t` - OptionalLit( - Option<Box<Expr<Label, Note, Embed>>>, - Vec<Expr<Label, Note, Embed>>, - ), + OptionalLit(Option<Box<Expr<Note, Embed>>>, Vec<Expr<Note, Embed>>), /// `Record [(k1, t1), (k2, t2)] ~ { k1 : t1, k2 : t1 }` - Record(BTreeMap<Label, Expr<Label, Note, Embed>>), + Record(BTreeMap<Label, Expr<Note, Embed>>), /// `RecordLit [(k1, v1), (k2, v2)] ~ { k1 = v1, k2 = v2 }` - RecordLit(BTreeMap<Label, Expr<Label, Note, Embed>>), + RecordLit(BTreeMap<Label, Expr<Note, Embed>>), /// `Union [(k1, t1), (k2, t2)] ~ < k1 : t1, k2 : t2 >` - Union(BTreeMap<Label, Expr<Label, Note, Embed>>), + Union(BTreeMap<Label, Expr<Note, Embed>>), /// `UnionLit (k1, v1) [(k2, t2), (k3, t3)] ~ < k1 = t1, k2 : t2, k3 : t3 >` UnionLit( Label, - Box<Expr<Label, Note, Embed>>, - BTreeMap<Label, Expr<Label, Note, Embed>>, + Box<Expr<Note, Embed>>, + BTreeMap<Label, Expr<Note, Embed>>, ), /// `Merge x y t ~ merge x y : t` Merge( - Box<Expr<Label, Note, Embed>>, - Box<Expr<Label, Note, Embed>>, - Option<Box<Expr<Label, Note, Embed>>>, + Box<Expr<Note, Embed>>, + Box<Expr<Note, Embed>>, + Option<Box<Expr<Note, Embed>>>, ), /// `Field e x ~ e.x` - Field(Box<Expr<Label, Note, Embed>>, Label), + Field(Box<Expr<Note, Embed>>, Label), /// Annotation on the AST. Unused for now but could hold e.g. file location information - Note(Note, Box<Expr<Label, Note, Embed>>), + Note(Note, Box<Expr<Note, Embed>>), /// Embeds an import or the result of resolving the import Embed(Embed), } @@ -296,49 +277,43 @@ pub enum Builtin { TextShow, } -impl From<Label> for V<Label> { +impl From<Label> for V { fn from(s: Label) -> Self { V(s, 0) } } -impl From<&'static str> for V<Label> { +impl From<&'static str> for V { fn from(s: &'static str) -> Self { V(s.into(), 0) } } -impl<'i, S, A> From<&'i str> for Expr<&'i str, S, A> { - fn from(s: &'i str) -> Self { - Expr::Var(V(s, 0)) - } -} - -impl<S, A> From<&'static str> for Expr<Label, S, A> { +impl<S, A> From<&'static str> for Expr<S, A> { fn from(s: &'static str) -> Self { Expr::Var(V(s.into(), 0)) } } -impl<Label, S, A> From<Builtin> for Expr<Label, S, A> { +impl<S, A> From<Builtin> for Expr<S, A> { fn from(t: Builtin) -> Self { Expr::Builtin(t) } } -impl<S, A> Expr<Label, S, A> { +impl<S, A> Expr<S, A> { pub fn map_shallow<T, B, F1, F2, F3, F4>( &self, map_expr: F1, map_note: F2, map_embed: F3, map_label: F4, - ) -> Expr<Label, T, B> + ) -> Expr<T, B> where A: Clone, T: Clone, S: Clone, - F1: Fn(&Self) -> Expr<Label, T, B>, + F1: Fn(&Self) -> Expr<T, B>, F2: FnOnce(&S) -> T, F3: FnOnce(&A) -> B, F4: Fn(&Label) -> Label, @@ -346,15 +321,13 @@ impl<S, A> Expr<Label, S, A> { map_shallow(self, map_expr, map_note, map_embed, map_label) } - pub fn map_embed<B, F>(&self, map_embed: &F) -> Expr<Label, S, B> + pub fn map_embed<B, F>(&self, map_embed: &F) -> Expr<S, B> where A: Clone, S: Clone, F: Fn(&A) -> B, { - let recurse = |e: &Expr<Label, S, A>| -> Expr<Label, S, B> { - e.map_embed(map_embed) - }; + let recurse = |e: &Expr<S, A>| -> Expr<S, B> { e.map_embed(map_embed) }; self.map_shallow(recurse, |x| x.clone(), map_embed, |x| x.clone()) } @@ -390,8 +363,8 @@ impl<S, A> Expr<Label, S, A> { } } -impl<S: Clone, A: Clone> Expr<Label, S, Expr<Label, S, A>> { - pub fn squash_embed(&self) -> Expr<Label, S, A> { +impl<S: Clone, A: Clone> Expr<S, Expr<S, A>> { + pub fn squash_embed(&self) -> Expr<S, A> { match self { Expr::Embed(e) => e.clone(), e => e.map_shallow( @@ -414,7 +387,7 @@ impl<S: Clone, A: Clone> Expr<Label, S, Expr<Label, S, A>> { // you add a new constructor to the syntax tree without adding a matching // case the corresponding builder. -impl<Label: Display, S, A: Display> Display for Expr<Label, S, A> { +impl<S, A: Display> Display for Expr<S, A> { fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> { // buildExprA use crate::Expr::*; @@ -430,7 +403,7 @@ impl<Label: Display, S, A: Display> Display for Expr<Label, S, A> { } } -impl<Label: Display, S, A: Display> Expr<Label, S, A> { +impl<S, A: Display> Expr<S, A> { fn fmt_b(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> { use crate::Expr::*; match self { @@ -726,7 +699,7 @@ impl Builtin { } } -impl<Label: Display> Display for V<Label> { +impl Display for V { fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> { let V(ref x, ref n) = *self; x.fmt(f)?; @@ -737,19 +710,19 @@ impl<Label: Display> Display for V<Label> { } } -pub fn pi<S, A, Name, Et, Ev>(var: Name, ty: Et, value: Ev) -> Expr<Label, S, A> +pub fn pi<S, A, Name, Et, Ev>(var: Name, ty: Et, value: Ev) -> Expr<S, A> where Name: Into<Label>, - Et: Into<Expr<Label, S, A>>, - Ev: Into<Expr<Label, S, A>>, + Et: Into<Expr<S, A>>, + Ev: Into<Expr<S, A>>, { Expr::Pi(var.into(), bx(ty.into()), bx(value.into())) } -pub fn app<Label, S, A, Ef, Ex>(f: Ef, x: Ex) -> Expr<Label, S, A> +pub fn app<S, A, Ef, Ex>(f: Ef, x: Ex) -> Expr<S, A> where - Ef: Into<Expr<Label, S, A>>, - Ex: Into<Expr<Label, S, A>>, + Ef: Into<Expr<S, A>>, + Ex: Into<Expr<S, A>>, { Expr::App(bx(f.into()), bx(x.into())) } @@ -783,24 +756,23 @@ fn add_ui(u: usize, i: isize) -> usize { } pub fn map_shallow<S, T, A, B, F1, F2, F3, F4>( - e: &Expr<Label, S, A>, + e: &Expr<S, A>, map: F1, map_note: F2, map_embed: F3, map_label: F4, -) -> Expr<Label, T, B> +) -> Expr<T, B> where A: Clone, S: Clone, T: Clone, - F1: Fn(&Expr<Label, S, A>) -> Expr<Label, T, B>, + F1: Fn(&Expr<S, A>) -> Expr<T, B>, F2: FnOnce(&S) -> T, F3: FnOnce(&A) -> B, F4: Fn(&Label) -> Label, { use crate::Expr::*; - let bxmap = - |x: &Expr<Label, S, A>| -> Box<Expr<Label, T, B>> { bx(map(x)) }; + let bxmap = |x: &Expr<S, A>| -> Box<Expr<T, B>> { bx(map(x)) }; let opt = |x| map_opt_box(x, &map); match *e { Const(k) => Const(k), @@ -959,11 +931,7 @@ where /// descend into a lambda or let expression that binds a variable of the same /// name in order to avoid shifting the bound variables by mistake. /// -pub fn shift<S, T, A: Clone>( - d: isize, - v: &V<Label>, - e: &Expr<Label, S, A>, -) -> Expr<Label, T, A> { +pub fn shift<S, T, A: Clone>(d: isize, v: &V, e: &Expr<S, A>) -> Expr<T, A> { use crate::Expr::*; let V(x, n) = v; match e { @@ -1039,15 +1007,12 @@ pub fn shift<S, T, A: Clone>( fn shift_op2<S, T, A, F>( f: F, d: isize, - v: &V<Label>, - a: &Expr<Label, S, A>, - b: &Expr<Label, S, A>, -) -> Expr<Label, T, A> + v: &V, + a: &Expr<S, A>, + b: &Expr<S, A>, +) -> Expr<T, A> where - F: FnOnce( - Box<Expr<Label, T, A>>, - Box<Expr<Label, T, A>>, - ) -> Expr<Label, T, A>, + F: FnOnce(Box<Expr<T, A>>, Box<Expr<T, A>>) -> Expr<T, A>, A: Clone, { map_op2(f, |x| bx(shift(d, v, x)), a, b) @@ -1059,11 +1024,7 @@ where /// subst x C B ~ B[x := C] /// ``` /// -pub fn subst<S, T, A>( - v: &V<Label>, - e: &Expr<Label, S, A>, - b: &Expr<Label, T, A>, -) -> Expr<Label, S, A> +pub fn subst<S, T, A>(v: &V, e: &Expr<S, A>, b: &Expr<T, A>) -> Expr<S, A> where S: Clone, A: Clone, @@ -1150,16 +1111,13 @@ where fn subst_op2<S, T, A, F>( f: F, - v: &V<Label>, - e: &Expr<Label, S, A>, - a: &Expr<Label, T, A>, - b: &Expr<Label, T, A>, -) -> Expr<Label, S, A> + v: &V, + e: &Expr<S, A>, + a: &Expr<T, A>, + b: &Expr<T, A>, +) -> Expr<S, A> where - F: FnOnce( - Box<Expr<Label, S, A>>, - Box<Expr<Label, S, A>>, - ) -> Expr<Label, S, A>, + F: FnOnce(Box<Expr<S, A>>, Box<Expr<S, A>>) -> Expr<S, A>, S: Clone, A: Clone, { |