Merge branch 'serde'

1 files changed, 46 insertions, 0 deletions

diff --git a/dhall/src/traits/deserialize.rs b/dhall/src/traits/deserialize.rs
new file mode 100644
index 0000000..1fbdfe1
--- /dev/null
+++ b/dhall/src/traits/deserialize.rs
@@ -0,0 +1,46 @@
+use crate::error::*;
+use crate::expr::*;
+
+pub trait Deserialize<'a>: Sized {
+    fn from_str(s: &'a str, ty: Option<&Type>) -> Result<Self>;
+}
+
+impl<'a> Deserialize<'a> for Parsed {
+    /// Simply parses the provided string. Ignores the
+    /// provided type.
+    fn from_str(s: &'a str, _: Option<&Type>) -> Result<Self> {
+        Ok(Parsed::parse_str(s)?)
+    }
+}
+
+impl<'a> Deserialize<'a> for Resolved {
+    /// Parses and resolves the provided string. Ignores the
+    /// provided type.
+    fn from_str(s: &'a str, ty: Option<&Type>) -> Result<Self> {
+        Ok(Parsed::from_str(s, ty)?.resolve()?)
+    }
+}
+
+impl<'a> Deserialize<'a> for Typed {
+    /// Parses, resolves and typechecks the provided string.
+    fn from_str(s: &'a str, ty: Option<&Type>) -> Result<Self> {
+        let resolved = Resolved::from_str(s, ty)?;
+        match ty {
+            None => Ok(resolved.typecheck()?),
+            Some(t) => Ok(resolved.typecheck_with(t)?),
+        }
+    }
+}
+
+impl<'a> Deserialize<'a> for Normalized {
+    /// Parses, resolves, typechecks and normalizes the provided string.
+    fn from_str(s: &'a str, ty: Option<&Type>) -> Result<Self> {
+        Ok(Typed::from_str(s, ty)?.normalize())
+    }
+}
+
+impl<'a> Deserialize<'a> for Type {
+    fn from_str(s: &'a str, ty: Option<&Type>) -> Result<Self> {
+        Ok(Normalized::from_str(s, ty)?.into_type())
+    }
+}