Fully fledged lambdas, along with efficiency tweaks across the ast

src/stl.rs

@@ -492,6 +492,17 @@ pub fn static_stdlib(syms: &mut SymTable) -> Result<(), String> {
         },
     );
 
+    syms.insert(
+        "lambda".to_string(),
+        Symbol {
+            name: String::from("lambda"),
+            args: Args::Lazy(2),
+            conditional_branches: true,
+            docs: decl::LAMBDA_DOCSTRING.to_string(),
+            value: ValueType::Internal(Rc::new(decl::lambda_callback)),
+        }
+    );
+
     Ok(())
 }