feat(tvix/eval): add initial value representation r/4403

Change-Id: I427a04e89994662df2750dffe21991bad48aab15
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6066
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>

2 files changed, 11 insertions, 0 deletions

diff --git a/tvix/eval/src/main.rs b/tvix/eval/src/main.rs
index 8192965a8b..7cc5a380e5 100644
--- a/tvix/eval/src/main.rs
+++ b/tvix/eval/src/main.rs
@@ -6,6 +6,7 @@ use std::{
 
 mod errors;
 mod eval;
+mod value;
 
 fn main() {
     let mut args = env::args();
diff --git a/tvix/eval/src/value.rs b/tvix/eval/src/value.rs
new file mode 100644
index 0000000000..037284b144
--- /dev/null
+++ b/tvix/eval/src/value.rs
@@ -0,0 +1,10 @@
+//! This module implements the backing representation of runtime
+//! values in the Nix language.
+
+#[derive(Clone, Copy, Debug, PartialEq)]
+pub enum Value {
+    Null,
+    Bool(bool),
+    Integer(i64),
+    Float(f64),
+}