diff options
Diffstat (limited to 'dhall_core/src/core.rs')
| -rw-r--r-- | dhall_core/src/core.rs | 140 |
1 files changed, 127 insertions, 13 deletions
diff --git a/dhall_core/src/core.rs b/dhall_core/src/core.rs index b3ba142..8ce9715 100644 --- a/dhall_core/src/core.rs +++ b/dhall_core/src/core.rs @@ -1,6 +1,8 @@ #![allow(non_snake_case)] use std::collections::BTreeMap; use std::fmt::{self, Display}; +use std::iter::FromIterator; +use std::ops::Add; use std::path::PathBuf; use std::rc::Rc; @@ -171,6 +173,112 @@ pub enum BinOp { ListAppend, } +#[derive(Debug, Clone, PartialEq)] +pub struct InterpolatedText<Note, Embed> { + head: String, + tail: Vec<(Expr<Note, Embed>, String)>, +} + +impl<N, E> From<(String, Vec<(Expr<N, E>, String)>)> + for InterpolatedText<N, E> +{ + fn from(x: (String, Vec<(Expr<N, E>, String)>)) -> Self { + InterpolatedText { + head: x.0, + tail: x.1, + } + } +} + +impl<N, E> From<String> for InterpolatedText<N, E> { + fn from(s: String) -> Self { + InterpolatedText { + head: s, + tail: vec![], + } + } +} + +// TODO: merge both when we move to Rc<> +// This one is needed when parsing, because we need to own the Expr +pub enum OwnedInterpolatedTextContents<'a, Note, Embed> { + Text(&'a str), + Expr(Expr<Note, Embed>), +} + +// This one is needed everywhere else, because we don't want Clone traits bounds +// everywhere +pub enum BorrowedInterpolatedTextContents<'a, Note, Embed> { + Text(&'a str), + Expr(&'a Expr<Note, Embed>), +} + +impl<'a, N: Clone + 'a, E: Clone + 'a> BorrowedInterpolatedTextContents<'a, N, E> { + pub fn to_owned(self) -> OwnedInterpolatedTextContents<'a, N, E> { + match self { + BorrowedInterpolatedTextContents::Text(s) => OwnedInterpolatedTextContents::Text(s), + BorrowedInterpolatedTextContents::Expr(e) => OwnedInterpolatedTextContents::Expr(e.clone()), + } + } +} + +impl<N, E> InterpolatedText<N, E> { + pub fn map<N2, E2, F>(&self, mut f: F) -> InterpolatedText<N2, E2> + where + F: FnMut(&Expr<N, E>) -> Expr<N2, E2>, + { + InterpolatedText { + head: self.head.clone(), + tail: self.tail.iter().map(|(e, s)| (f(e), s.clone())).collect(), + } + } + + pub fn iter(&self) -> impl Iterator<Item = BorrowedInterpolatedTextContents<N, E>> { + use std::iter::once; + once(BorrowedInterpolatedTextContents::Text(self.head.as_ref())).chain( + self.tail.iter().flat_map(|(e, s)| { + once(BorrowedInterpolatedTextContents::Expr(e)) + .chain(once(BorrowedInterpolatedTextContents::Text(s))) + }), + ) + } +} + +impl<'a, N: Clone + 'a, E: Clone + 'a> + FromIterator<OwnedInterpolatedTextContents<'a, N, E>> + for InterpolatedText<N, E> +{ + fn from_iter<T>(iter: T) -> Self + where + T: IntoIterator<Item = OwnedInterpolatedTextContents<'a, N, E>>, + { + let mut res = InterpolatedText { + head: "".to_owned(), + tail: vec![], + }; + // let mut empty_string = "".to_owned(); + let mut crnt_str = &mut res.head; + for x in iter.into_iter() { + match x { + OwnedInterpolatedTextContents::Text(s) => crnt_str.push_str(s), + OwnedInterpolatedTextContents::Expr(e) => { + // crnt_str = &mut empty_string; + res.tail.push((e.clone(), "".to_owned())); + crnt_str = &mut res.tail.last_mut().unwrap().1; + } + } + } + res + } +} + +impl<N: Clone, E: Clone> Add for InterpolatedText<N, E> { + type Output = InterpolatedText<N, E>; + fn add(self, rhs: InterpolatedText<N, E>) -> Self::Output { + self.iter().chain(rhs.iter()).map(BorrowedInterpolatedTextContents::to_owned).collect() + } +} + /// Syntax tree for expressions #[derive(Debug, Clone, PartialEq)] pub enum Expr<Note, Embed> { @@ -215,7 +323,7 @@ pub enum Expr<Note, Embed> { /// `DoubleLit n ~ n` DoubleLit(Double), /// `TextLit t ~ t` - TextLit(Builder), + TextLit(InterpolatedText<Note, Embed>), /// `ListLit t [x, y, z] ~ [x, y, z] : List t` ListLit(Option<Box<Expr<Note, Embed>>>, Vec<Expr<Note, Embed>>), /// `OptionalLit t [e] ~ [e] : Optional t` @@ -358,13 +466,6 @@ impl<S, A> Expr<S, A> { _ => None, } } - - pub fn text_lit(&self) -> Option<String> { - match *self { - Expr::TextLit(ref t) => Some(t.clone()), // FIXME? - _ => None, - } - } } impl<S: Clone, A: Clone> Expr<S, Expr<S, A>> { @@ -570,7 +671,21 @@ impl<S, A: Display> Expr<S, A> { a.fmt(f) } &DoubleLit(a) => a.fmt(f), - &TextLit(ref a) => <String as fmt::Debug>::fmt(a, f), // FIXME Format with Haskell escapes + &TextLit(ref a) => { + for x in a.iter() { + match x { + BorrowedInterpolatedTextContents::Text(a) => { + <str as fmt::Debug>::fmt(a, f)? + } // TODO Format escapes properly + BorrowedInterpolatedTextContents::Expr(e) => { + f.write_str("${")?; + e.fmt(f)?; + f.write_str("}")?; + } + } + } + Ok(()) + } &Record(ref a) if a.is_empty() => f.write_str("{}"), &Record(ref a) => fmt_list("{ ", " }", a, f, |(k, t), f| { write!(f, "{} : {}", k, t) @@ -724,7 +839,6 @@ where Expr::App(bx(f.into()), bx(x.into())) } -pub type Builder = String; pub type Double = f64; pub type Int = isize; pub type Integer = isize; @@ -788,7 +902,7 @@ where NaturalLit(n) => NaturalLit(n), IntegerLit(n) => IntegerLit(n), DoubleLit(n) => DoubleLit(n), - TextLit(ref t) => TextLit(t.clone()), + TextLit(ref t) => TextLit(t.map(|e| map(e))), BinOp(o, ref x, ref y) => BinOp(o, bxmap(x), bxmap(y)), ListLit(ref t, ref es) => { let es = es.iter().map(&map).collect(); @@ -972,7 +1086,7 @@ pub fn shift<S, T, A: Clone>(d: isize, v: &V, e: &Expr<S, A>) -> Expr<T, A> { NaturalLit(a) => NaturalLit(*a), IntegerLit(a) => IntegerLit(*a), DoubleLit(a) => DoubleLit(*a), - TextLit(a) => TextLit(a.clone()), + TextLit(a) => TextLit(a.map(|e| shift(d, v, e))), ListLit(t, es) => ListLit( t.as_ref().map(|t| bx(shift(d, v, t))), es.iter().map(|e| shift(d, v, e)).collect(), @@ -1075,7 +1189,7 @@ where NaturalLit(a) => NaturalLit(*a), IntegerLit(a) => IntegerLit(*a), DoubleLit(a) => DoubleLit(*a), - TextLit(a) => TextLit(a.clone()), + TextLit(a) => TextLit(a.map(|b| subst(v, e, b))), ListLit(a, b) => { let a2 = a.as_ref().map(|a| bx(subst(v, e, a))); let b2 = b.iter().map(|be| subst(v, e, be)).collect(); |