use std::fmt::Display; use std::path::Path; use crate::error::{EncodeError, Error, ImportError, TypeError}; use crate::semantics::core::value::Value; use crate::semantics::core::value::ValueKind; use crate::syntax::binary; use crate::syntax::{Builtin, Const, Expr}; use resolve::ImportRoot; pub(crate) mod normalize; pub(crate) mod parse; pub(crate) mod resolve; pub(crate) mod typecheck; pub type ParsedExpr = Expr; pub type DecodedExpr = Expr; pub type ResolvedExpr = Expr; pub type NormalizedExpr = Expr; #[derive(Debug, Clone)] pub struct Parsed(ParsedExpr, ImportRoot); /// An expression where all imports have been resolved /// /// Invariant: there must be no `Import` nodes or `ImportAlt` operations left. #[derive(Debug, Clone)] pub struct Resolved(ResolvedExpr); /// A typed expression #[derive(Debug, Clone)] pub struct Typed(Value); /// A normalized expression. /// /// Invariant: the contained Typed expression must be in normal form, #[derive(Debug, Clone)] pub struct Normalized(Typed); /// Controls conversion from `Value` to `Expr` #[derive(Copy, Clone)] pub(crate) struct ToExprOptions { /// Whether to convert all variables to `_` pub(crate) alpha: bool, /// Whether to normalize before converting pub(crate) normalize: bool, } impl Parsed { pub fn parse_file(f: &Path) -> Result { parse::parse_file(f) } pub fn parse_str(s: &str) -> Result { parse::parse_str(s) } pub fn parse_binary_file(f: &Path) -> Result { parse::parse_binary_file(f) } pub fn parse_binary(data: &[u8]) -> Result { parse::parse_binary(data) } pub fn resolve(self) -> Result { resolve::resolve(self) } pub fn skip_resolve(self) -> Result { resolve::skip_resolve_expr(self) } pub fn encode(&self) -> Result, EncodeError> { binary::encode(&self.0) } /// Converts a value back to the corresponding AST expression. pub fn to_expr(&self) -> ParsedExpr { self.0.clone() } } impl Resolved { pub fn typecheck(self) -> Result { Ok(typecheck::typecheck(self.0)?.into_typed()) } pub fn typecheck_with(self, ty: &Typed) -> Result { Ok(typecheck::typecheck_with(self.0, ty.normalize_to_expr())? .into_typed()) } /// Converts a value back to the corresponding AST expression. pub fn to_expr(&self) -> ResolvedExpr { self.0.clone() } } impl Typed { /// Reduce an expression to its normal form, performing beta reduction pub fn normalize(mut self) -> Normalized { self.normalize_mut(); Normalized(self) } pub(crate) fn from_const(c: Const) -> Self { Typed(Value::from_const(c)) } pub(crate) fn from_kind_and_type(v: ValueKind, t: Typed) -> Self { Typed(Value::from_kind_and_type(v, t.into_value())) } pub(crate) fn from_value(th: Value) -> Self { Typed(th) } pub(crate) fn const_type() -> Self { Typed::from_const(Const::Type) } /// Converts a value back to the corresponding AST expression. pub fn to_expr(&self) -> ResolvedExpr { self.0.to_expr(ToExprOptions { alpha: false, normalize: false, }) } /// Converts a value back to the corresponding AST expression, beta-normalizing in the process. pub fn normalize_to_expr(&self) -> NormalizedExpr { self.0.to_expr(ToExprOptions { alpha: false, normalize: true, }) } /// Converts a value back to the corresponding AST expression, (alpha,beta)-normalizing in the /// process. pub(crate) fn normalize_to_expr_alpha(&self) -> NormalizedExpr { self.0.to_expr(ToExprOptions { alpha: true, normalize: true, }) } pub(crate) fn to_value(&self) -> Value { self.0.clone() } pub(crate) fn into_value(self) -> Value { self.0 } pub(crate) fn normalize_mut(&mut self) { self.0.normalize_mut() } pub(crate) fn get_type(&self) -> Result { Ok(self.0.get_type()?.into_typed()) } pub fn make_builtin_type(b: Builtin) -> Self { Typed::from_value(Value::from_builtin(b)) } pub fn make_optional_type(t: Typed) -> Self { Typed::from_value( Value::from_builtin(Builtin::Optional).app(t.to_value()), ) } pub fn make_list_type(t: Typed) -> Self { Typed::from_value(Value::from_builtin(Builtin::List).app(t.to_value())) } pub fn make_record_type( kts: impl Iterator, ) -> Self { Typed::from_kind_and_type( ValueKind::RecordType( kts.map(|(k, t)| (k.into(), t.into_value())).collect(), ), Typed::const_type(), ) } pub fn make_union_type( kts: impl Iterator)>, ) -> Self { Typed::from_kind_and_type( ValueKind::UnionType( kts.map(|(k, t)| (k.into(), t.map(|t| t.into_value()))) .collect(), ), Typed::const_type(), ) } } impl Normalized { pub fn encode(&self) -> Result, EncodeError> { binary::encode(&self.to_expr()) } pub(crate) fn to_expr(&self) -> NormalizedExpr { self.0.normalize_to_expr() } pub(crate) fn to_expr_alpha(&self) -> NormalizedExpr { self.0.normalize_to_expr_alpha() } pub(crate) fn into_typed(self) -> Typed { self.0 } } macro_rules! derive_traits_for_wrapper_struct { ($ty:ident) => { impl std::cmp::PartialEq for $ty { fn eq(&self, other: &Self) -> bool { self.0 == other.0 } } impl std::cmp::Eq for $ty {} impl std::fmt::Display for $ty { fn fmt( &self, f: &mut std::fmt::Formatter, ) -> Result<(), std::fmt::Error> { self.0.fmt(f) } } }; } derive_traits_for_wrapper_struct!(Parsed); derive_traits_for_wrapper_struct!(Resolved); derive_traits_for_wrapper_struct!(Normalized); impl std::hash::Hash for Normalized { fn hash(&self, state: &mut H) where H: std::hash::Hasher, { if let Ok(vec) = self.encode() { vec.hash(state) } } } impl Eq for Typed {} impl PartialEq for Typed { fn eq(&self, other: &Self) -> bool { self.0 == other.0 } } impl Display for Typed { fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> { self.to_expr().fmt(f) } }