Most base expressions work.

src/syntax/name.rs

@@ -0,0 +1,60 @@
+use crate::syntax::{Located, Location};
+use std::cmp;
+use std::fmt;
+use std::hash;
+use std::sync::atomic::{AtomicU64, Ordering};
+
+static IDENTIFIER_COUNTER: AtomicU64 = AtomicU64::new(0);
+
+#[derive(Debug)]
+pub struct Name {
+    printable: String,
+    identifier: u64,
+    location: Option<Location>,
+}
+
+impl cmp::PartialEq for Name {
+    fn eq(&self, other: &Self) -> bool {
+        self.identifier == other.identifier
+    }
+}
+
+impl cmp::Eq for Name {}
+
+impl hash::Hash for Name {
+    fn hash<H: hash::Hasher>(&self, state: &mut H) {
+        self.identifier.hash(state);
+    }
+}
+
+impl fmt::Display for Name {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}:{}", self.printable, self.identifier)
+    }
+}
+
+impl Name {
+    pub fn new<S: ToString>(location: Location, s: S) -> Name {
+        let my_id = IDENTIFIER_COUNTER.fetch_add(1, Ordering::SeqCst);
+        Name {
+            printable: s.to_string(),
+            identifier: my_id,
+            location: Some(location),
+        }
+    }
+
+    pub fn gensym(base: &'static str) -> Name {
+        let formatted = format!("<{base}>");
+        let my_id = IDENTIFIER_COUNTER.fetch_add(1, Ordering::SeqCst);
+
+        Name {
+            printable: formatted,
+            identifier: my_id,
+            location: None,
+        }
+    }
+
+    pub fn as_printed(&self) -> &str {
+        self.printable.as_str()
+    }
+}