forked from Orchid/orchid
62 lines
1.5 KiB
Rust
62 lines
1.5 KiB
Rust
use orchid_base::error::{OrcErr, OrcRes, mk_err};
|
|
use orchid_base::intern;
|
|
use orchid_base::location::Pos;
|
|
|
|
use crate::atom::{AtomicFeatures, ToAtom, TypAtom};
|
|
use crate::expr::{Expr, atom, bot};
|
|
use crate::system::downcast_atom;
|
|
|
|
pub trait TryFromExpr: Sized {
|
|
fn try_from_expr(expr: Expr) -> OrcRes<Self>;
|
|
}
|
|
|
|
impl TryFromExpr for Expr {
|
|
fn try_from_expr(expr: Expr) -> OrcRes<Self> { Ok(expr) }
|
|
}
|
|
|
|
impl<T: TryFromExpr, U: TryFromExpr> TryFromExpr for (T, U) {
|
|
fn try_from_expr(expr: Expr) -> OrcRes<Self> {
|
|
Ok((T::try_from_expr(expr.clone())?, U::try_from_expr(expr)?))
|
|
}
|
|
}
|
|
|
|
async fn err_not_atom(pos: Pos) -> OrcErr {
|
|
mk_err(intern!(str: "Expected an atom").await, "This expression is not an atom", [pos.into()])
|
|
}
|
|
|
|
async fn err_type(pos: Pos) -> OrcErr {
|
|
mk_err(intern!(str: "Type error").await, "The atom is a different type than expected", [
|
|
pos.into()
|
|
])
|
|
}
|
|
|
|
impl<A: AtomicFeatures> TryFromExpr for TypAtom<'_, A> {
|
|
async fn try_from_expr(expr: Expr) -> OrcRes<Self> {
|
|
match expr.foreign_atom() {
|
|
Err(ex) => Err(err_not_atom(ex.pos.clone()).await.into()),
|
|
Ok(f) => match downcast_atom(f) \.map_err(|f| err_type(f.pos).into()),
|
|
}
|
|
}
|
|
}
|
|
|
|
pub trait ToExpr {
|
|
fn to_expr(self) -> Expr;
|
|
}
|
|
|
|
impl ToExpr for Expr {
|
|
fn to_expr(self) -> Expr { self }
|
|
}
|
|
|
|
impl<T: ToExpr> ToExpr for OrcRes<T> {
|
|
fn to_expr(self) -> Expr {
|
|
match self {
|
|
Err(e) => bot(e),
|
|
Ok(t) => t.to_expr(),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<A: ToAtom> ToExpr for A {
|
|
fn to_expr(self) -> Expr { atom(self) }
|
|
}
|