diff options
Diffstat (limited to 'dhall_generator/src/dhall_expr.rs')
-rw-r--r-- | dhall_generator/src/dhall_expr.rs | 205 |
1 files changed, 0 insertions, 205 deletions
diff --git a/dhall_generator/src/dhall_expr.rs b/dhall_generator/src/dhall_expr.rs deleted file mode 100644 index d0c5733..0000000 --- a/dhall_generator/src/dhall_expr.rs +++ /dev/null @@ -1,205 +0,0 @@ -extern crate proc_macro; -use dhall_core::context::Context; -use dhall_core::*; -use proc_macro2::TokenStream; -use quote::quote; -use std::collections::BTreeMap; - -pub fn expr(input: proc_macro::TokenStream) -> proc_macro::TokenStream { - let input_str = input.to_string(); - let expr: SubExpr<X, Import> = parse_expr(&input_str).unwrap(); - let no_import = - |_: &Import| -> X { panic!("Don't use import in dhall::expr!()") }; - let expr = expr.as_ref().map_embed(&no_import); - let output = quote_expr(&expr, &Context::new()); - output.into() -} - -pub fn subexpr(input: proc_macro::TokenStream) -> proc_macro::TokenStream { - let input_str = input.to_string(); - let expr: SubExpr<X, Import> = parse_expr(&input_str).unwrap(); - let no_import = - |_: &Import| -> X { panic!("Don't use import in dhall::subexpr!()") }; - let expr = expr.as_ref().map_embed(&no_import); - let output = quote_subexpr(&rc(expr), &Context::new()); - output.into() -} - -// Returns an expression of type ExprF<T, _, _>, where T is the -// type of the subexpressions after interpolation. -pub fn quote_exprf<TS>(expr: ExprF<TS, Label, X, X>) -> TokenStream -where - TS: quote::ToTokens + std::fmt::Debug, -{ - let quote_map = |m: BTreeMap<Label, TS>| -> TokenStream { - let entries = m.into_iter().map(|(k, v)| { - let k = quote_label(&k); - quote!(m.insert(#k, #v);) - }); - quote! { { - use std::collections::BTreeMap; - let mut m = BTreeMap::new(); - #( #entries )* - m - } } - }; - - let quote_vec = |e: Vec<TS>| -> TokenStream { - quote! { vec![ #(#e),* ] } - }; - - use dhall_core::ExprF::*; - match expr { - Var(_) => unreachable!(), - Pi(x, t, b) => { - let x = quote_label(&x); - quote! { dhall_core::ExprF::Pi(#x, #t, #b) } - } - Lam(x, t, b) => { - let x = quote_label(&x); - quote! { dhall_core::ExprF::Lam(#x, #t, #b) } - } - App(f, a) => { - let a = quote_vec(a); - quote! { dhall_core::ExprF::App(#f, #a) } - } - Const(c) => { - let c = quote_const(c); - quote! { dhall_core::ExprF::Const(#c) } - } - Builtin(b) => { - let b = quote_builtin(b); - quote! { dhall_core::ExprF::Builtin(#b) } - } - BinOp(o, a, b) => { - let o = quote_binop(o); - quote! { dhall_core::ExprF::BinOp(#o, #a, #b) } - } - NaturalLit(n) => { - quote! { dhall_core::ExprF::NaturalLit(#n) } - } - BoolLit(b) => { - quote! { dhall_core::ExprF::BoolLit(#b) } - } - EmptyOptionalLit(x) => { - quote! { dhall_core::ExprF::EmptyOptionalLit(#x) } - } - NEOptionalLit(x) => { - quote! { dhall_core::ExprF::NEOptionalLit(#x) } - } - EmptyListLit(t) => { - quote! { dhall_core::ExprF::EmptyListLit(#t) } - } - NEListLit(es) => { - let es = quote_vec(es); - quote! { dhall_core::ExprF::NEListLit(#es) } - } - RecordType(m) => { - let m = quote_map(m); - quote! { dhall_core::ExprF::RecordType(#m) } - } - RecordLit(m) => { - let m = quote_map(m); - quote! { dhall_core::ExprF::RecordLit(#m) } - } - UnionType(m) => { - let m = quote_map(m); - quote! { dhall_core::ExprF::UnionType(#m) } - } - e => unimplemented!("{:?}", e), - } -} - -// Returns an expression of type SubExpr<_, _>. Expects interpolated variables -// to be of type SubExpr<_, _>. -fn quote_subexpr( - expr: &SubExpr<X, X>, - ctx: &Context<Label, ()>, -) -> TokenStream { - use dhall_core::ExprF::*; - match expr.as_ref().map_ref( - |e| quote_subexpr(e, ctx), - |l, e| quote_subexpr(e, &ctx.insert(l.clone(), ())), - |_| unreachable!(), - |_| unreachable!(), - |l| l.clone(), - ) { - Var(V(ref s, n)) => { - match ctx.lookup(s, n) { - // Non-free variable; interpolates as itself - Some(()) => { - let s: String = s.into(); - let var = quote! { dhall_core::V(#s.into(), #n) }; - bx(quote! { dhall_core::ExprF::Var(#var) }) - } - // Free variable; interpolates as a rust variable - None => { - let s: String = s.into(); - // TODO: insert appropriate shifts ? - let v: TokenStream = s.parse().unwrap(); - quote! { { - let x: dhall_core::SubExpr<_, _> = #v.clone(); - x - } } - } - } - } - e => bx(quote_exprf(e)), - } -} - -// Returns an expression of type Expr<_, _>. Expects interpolated variables -// to be of type SubExpr<_, _>. -fn quote_expr(expr: &Expr<X, X>, ctx: &Context<Label, ()>) -> TokenStream { - use dhall_core::ExprF::*; - match expr.map_ref( - |e| quote_subexpr(e, ctx), - |l, e| quote_subexpr(e, &ctx.insert(l.clone(), ())), - |_| unreachable!(), - |_| unreachable!(), - |l| l.clone(), - ) { - Var(V(ref s, n)) => { - match ctx.lookup(s, n) { - // Non-free variable; interpolates as itself - Some(()) => { - let s: String = s.into(); - let var = quote! { dhall_core::V(#s.into(), #n) }; - quote! { dhall_core::ExprF::Var(#var) } - } - // Free variable; interpolates as a rust variable - None => { - let s: String = s.into(); - // TODO: insert appropriate shifts ? - let v: TokenStream = s.parse().unwrap(); - quote! { { - let x: dhall_core::SubExpr<_, _> = #v.clone(); - x.unroll() - } } - } - } - } - e => quote_exprf(e), - } -} - -fn quote_builtin(b: Builtin) -> TokenStream { - format!("dhall_core::Builtin::{:?}", b).parse().unwrap() -} - -fn quote_const(c: Const) -> TokenStream { - format!("dhall_core::Const::{:?}", c).parse().unwrap() -} - -fn quote_binop(b: BinOp) -> TokenStream { - format!("dhall_core::BinOp::{:?}", b).parse().unwrap() -} - -fn quote_label(l: &Label) -> TokenStream { - let l = String::from(l); - quote! { dhall_core::Label::from(#l) } -} - -fn bx(x: TokenStream) -> TokenStream { - quote! { dhall_core::bx(#x) } -} |