diff options
Diffstat (limited to '')
| -rw-r--r-- | dhall/src/syntax/ast/visitor.rs | 100 |
1 files changed, 30 insertions, 70 deletions
diff --git a/dhall/src/syntax/ast/visitor.rs b/dhall/src/syntax/ast/visitor.rs index 0a0c5ef..7244d0a 100644 --- a/dhall/src/syntax/ast/visitor.rs +++ b/dhall/src/syntax/ast/visitor.rs @@ -1,22 +1,13 @@ +use itertools::Itertools; use std::iter::FromIterator; use crate::syntax::*; -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() -} - 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, - }) + x.as_ref().map(f).transpose() } fn dupmap<'a, SE1, SE2, T, Err>( @@ -30,27 +21,6 @@ where x.into_iter().map(|(k, x)| Ok((k.clone(), f(x)?))).collect() } -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 - SE1: 'a, - T: FromIterator<(Label, Option<SE2>)>, -{ - x.into_iter() - .map(|(k, x)| { - Ok(( - k.clone(), - match x { - Some(x) => Some(f(x)?), - None => None, - }, - )) - }) - .collect() -} - pub fn visit_ref<'a, F, SE1, SE2, Err>( input: &'a ExprKind<SE1>, mut f: F, @@ -60,54 +30,44 @@ where { // Can't use closures because of borrowing rules macro_rules! expr { + () => { + |e| Ok(expr!(e)) + }; ($e:expr) => { - f(None, $e) + f(None, $e)? }; ($l:expr, $e:expr) => { - f(Some($l), $e) + f(Some($l), $e)? + }; + } + macro_rules! opt { + () => { + |e| Ok(opt!(e)) + }; + ($e:expr) => { + opt($e, |e| Ok(expr!(e)))? }; } use crate::syntax::ExprKind::*; Ok(match input { Var(v) => Var(v.clone()), - Lam(l, t, e) => { - let t = expr!(t)?; - let e = expr!(l, e)?; - Lam(l.clone(), t, e) - } - Pi(l, t, 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| expr!(e))?; - let a = expr!(a)?; - let e = expr!(l, e)?; - Let(l.clone(), t, a, e) - } - App(f, a) => App(expr!(f)?, expr!(a)?), - Annot(x, t) => Annot(expr!(x)?, expr!(t)?), + Lam(l, t, e) => Lam(l.clone(), expr!(t), expr!(l, e)), + Pi(l, t, e) => Pi(l.clone(), expr!(t), expr!(l, e)), + Let(l, t, a, e) => Let(l.clone(), opt!(t), expr!(a), expr!(l, e)), Const(k) => Const(*k), - Builtin(v) => Builtin(*v), Num(n) => Num(n.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))?), + Builtin(v) => Builtin(*v), + TextLit(t) => TextLit(t.traverse_ref(expr!())?), + SomeLit(e) => SomeLit(expr!(e)), + EmptyListLit(t) => EmptyListLit(expr!(t)), + NEListLit(es) => NEListLit(es.iter().map(expr!()).try_collect()?), + RecordType(kts) => RecordType(dupmap(kts, expr!())?), + RecordLit(kvs) => RecordLit(dupmap(kvs, expr!())?), + UnionType(kts) => UnionType(dupmap(kts, opt!())?), + Op(op) => Op(op.traverse_ref(expr!())?), + Annot(x, t) => Annot(expr!(x), expr!(t)), + Assert(e) => Assert(expr!(e)), + Import(i) => Import(i.traverse_ref(expr!())?), }) } |