Add Spanned type

xlang/xlang_frontend/src/span.rs

@@ -1,3 +1,9 @@
+use core::ops::{Deref, DerefMut};
+
+use xlang::abi::ops::{ChangeOutputType, Residual, Try};
+
+use xlang::abi::try_;
+
 use crate::symbol::Symbol;
 
 #[derive(Copy, Clone, Debug, Hash, PartialEq, Eq)]
@@ -91,3 +97,77 @@ impl<H> Span<H> {
         self.is_empty() && self.begin.is_synthetic()
     }
 }
+
+#[derive(Copy, Clone, Debug, Hash, PartialEq, Eq)]
+pub struct Spanned<T, H> {
+    val: T,
+    span: Span<H>,
+}
+
+impl<T, H> Deref for Spanned<T, H> {
+    type Target = T;
+
+    fn deref(&self) -> &T {
+        &self.val
+    }
+}
+
+impl<T, H> DerefMut for Spanned<T, H> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.val
+    }
+}
+
+impl<T, H> Spanned<T, H> {
+    pub const fn new(val: T, span: Span<H>) -> Self {
+        Self { val, span }
+    }
+
+    pub fn into_inner(self) -> T {
+        self.val
+    }
+
+    pub const fn span(&self) -> &Span<H> {
+        &self.span
+    }
+
+    pub fn map<U, F: FnOnce(T) -> U>(self, f: F) -> Spanned<U, H> {
+        let Self { val, span } = self;
+
+        Spanned::new(f(val), span)
+    }
+
+    pub fn try_map<R: Try, F: FnOnce(T) -> R>(
+        self,
+        f: F,
+    ) -> ChangeOutputType<R, Spanned<R::Output, H>>
+    where
+        R::Residual: Residual<Spanned<R::Output, H>>,
+    {
+        let Self { val, span } = self;
+
+        Try::from_output(Spanned::new(try_!(f(val)), span))
+    }
+
+    pub fn copy_span<U, F: FnOnce(&T) -> U>(&self, f: F) -> Spanned<U, H>
+    where
+        H: Copy,
+    {
+        let Self { val, span } = self;
+
+        Spanned::new(f(val), *span)
+    }
+
+    pub fn try_copy_span<R: Try, F: FnOnce(&T) -> R>(
+        &self,
+        f: F,
+    ) -> ChangeOutputType<R, Spanned<R::Output, H>>
+    where
+        R::Residual: Residual<Spanned<R::Output, H>>,
+        H: Copy,
+    {
+        let Self { val, span } = self;
+
+        Try::from_output(Spanned::new(try_!(f(val)), *span))
+    }
+}