diff options
Diffstat (limited to 'dhall/src/syntax')
-rw-r--r-- | dhall/src/syntax/ast/expr.rs | 151 |
1 files changed, 76 insertions, 75 deletions
diff --git a/dhall/src/syntax/ast/expr.rs b/dhall/src/syntax/ast/expr.rs index 7ac342d..a85b837 100644 --- a/dhall/src/syntax/ast/expr.rs +++ b/dhall/src/syntax/ast/expr.rs @@ -6,46 +6,10 @@ pub type Integer = isize; pub type Natural = usize; pub type Double = NaiveDouble; -pub fn trivial_result<T>(x: Result<T, !>) -> T { - match x { - Ok(x) => x, - Err(e) => e, - } -} - /// Double with bitwise equality #[derive(Debug, Copy, Clone)] pub struct NaiveDouble(f64); -impl PartialEq for NaiveDouble { - fn eq(&self, other: &Self) -> bool { - self.0.to_bits() == other.0.to_bits() - } -} - -impl Eq for NaiveDouble {} - -impl std::hash::Hash for NaiveDouble { - fn hash<H>(&self, state: &mut H) - where - H: std::hash::Hasher, - { - self.0.to_bits().hash(state) - } -} - -impl From<f64> for NaiveDouble { - fn from(x: f64) -> Self { - NaiveDouble(x) - } -} - -impl From<NaiveDouble> for f64 { - fn from(x: NaiveDouble) -> f64 { - x.0 - } -} - /// Constants for a pure type system #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)] pub enum Const { @@ -62,18 +26,6 @@ pub enum Const { #[derive(Debug, Clone, PartialEq, Eq, Hash)] pub struct V<Label>(pub Label, pub usize); -// This is only for the specific `Label` type, not generic -impl From<Label> for V<Label> { - fn from(x: Label) -> V<Label> { - V(x, 0) - } -} -impl<'a> From<&'a Label> for V<Label> { - fn from(x: &'a Label) -> V<Label> { - V(x.clone(), 0) - } -} - // Definition order must match precedence order for // pretty-printing to work correctly #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)] @@ -146,23 +98,6 @@ pub struct Expr<Embed>(Box<(RawExpr<Embed>, Span)>); pub type RawExpr<Embed> = ExprKind<Expr<Embed>, Embed>; -impl<Embed: PartialEq> std::cmp::PartialEq for Expr<Embed> { - fn eq(&self, other: &Self) -> bool { - self.0.as_ref().0 == other.0.as_ref().0 - } -} - -impl<Embed: Eq> std::cmp::Eq for Expr<Embed> {} - -impl<Embed: std::hash::Hash> std::hash::Hash for Expr<Embed> { - fn hash<H>(&self, state: &mut H) - where - H: std::hash::Hasher, - { - (self.0).0.hash(state) - } -} - /// Syntax tree for expressions // Having the recursion out of the enum definition enables writing // much more generic code and improves pattern-matching behind @@ -350,16 +285,6 @@ impl<E> Expr<E> { } } -/// Add an isize to an usize -/// Returns `None` on over/underflow -fn add_ui(u: usize, i: isize) -> Option<usize> { - Some(if i < 0 { - u.checked_sub(i.checked_neg()? as usize)? - } else { - u.checked_add(i as usize)? - }) -} - impl<Label: PartialEq + Clone> V<Label> { pub fn shift(&self, delta: isize, var: &V<Label>) -> Option<Self> { let V(x, n) = var; @@ -375,3 +300,79 @@ impl<Label: PartialEq + Clone> V<Label> { self.shift(-1, &V(x.clone(), 0)) } } + +pub fn trivial_result<T>(x: Result<T, !>) -> T { + match x { + Ok(x) => x, + Err(e) => e, + } +} + +/// Add an isize to an usize +/// Returns `None` on over/underflow +fn add_ui(u: usize, i: isize) -> Option<usize> { + Some(if i < 0 { + u.checked_sub(i.checked_neg()? as usize)? + } else { + u.checked_add(i as usize)? + }) +} + +impl PartialEq for NaiveDouble { + fn eq(&self, other: &Self) -> bool { + self.0.to_bits() == other.0.to_bits() + } +} + +impl Eq for NaiveDouble {} + +impl std::hash::Hash for NaiveDouble { + fn hash<H>(&self, state: &mut H) + where + H: std::hash::Hasher, + { + self.0.to_bits().hash(state) + } +} + +impl From<f64> for NaiveDouble { + fn from(x: f64) -> Self { + NaiveDouble(x) + } +} + +impl From<NaiveDouble> for f64 { + fn from(x: NaiveDouble) -> f64 { + x.0 + } +} + +// This is only for the specific `Label` type, not generic +impl From<Label> for V<Label> { + fn from(x: Label) -> V<Label> { + V(x, 0) + } +} + +impl<'a> From<&'a Label> for V<Label> { + fn from(x: &'a Label) -> V<Label> { + V(x.clone(), 0) + } +} + +impl<Embed: PartialEq> std::cmp::PartialEq for Expr<Embed> { + fn eq(&self, other: &Self) -> bool { + self.0.as_ref().0 == other.0.as_ref().0 + } +} + +impl<Embed: Eq> std::cmp::Eq for Expr<Embed> {} + +impl<Embed: std::hash::Hash> std::hash::Hash for Expr<Embed> { + fn hash<H>(&self, state: &mut H) + where + H: std::hash::Hasher, + { + (self.0).0.hash(state) + } +} |