introduce tags, structs, and reticles

this was meant to be split into smaller changes, but I realised I edited my existing revision too late.

crates/haku/tests/language.rs

@@ -2,7 +2,7 @@ use std::error::Error;
 
 use haku::{
     ast::{dump::dump, Ast},
-    bytecode::{Chunk, Defs},
+    bytecode::{Chunk, Defs, DefsLimits},
     compiler::{compile_expr, Compiler, Source},
     lexer::{lex, Lexer},
     parser::{self, Parser, ParserLimits},
@@ -14,7 +14,7 @@ use haku::{
 };
 
 fn eval(code: &str) -> Result<Value, Box<dyn Error>> {
-    let mut system = System::new(1);
+    let mut system = System::new(2);
 
     let code = SourceCode::unlimited_len(code);
 
@@ -32,7 +32,10 @@ fn eval(code: &str) -> Result<Value, Box<dyn Error>> {
         system: &system,
     };
 
-    let mut defs = Defs::new(256);
+    let mut defs = Defs::new(&DefsLimits {
+        max_defs: 256,
+        max_tags: 256,
+    });
     let mut chunk = Chunk::new(65536).unwrap();
     let mut compiler = Compiler::new(&mut defs, &mut chunk);
     compile_expr(&mut compiler, &src, root)?;
@@ -70,7 +73,7 @@ fn eval(code: &str) -> Result<Value, Box<dyn Error>> {
     println!("closure spec: {closure_spec:?}");
 
     let closure = vm.create_ref(Ref::Closure(Closure::chunk(chunk_id, closure_spec)))?;
-    let result = vm.run(&system, closure)?;
+    let result = vm.run(&system, closure, &[])?;
 
     println!("used fuel: {}", limits.fuel - vm.remaining_fuel());
 
@@ -281,3 +284,11 @@ fn issue_78() {
     "#;
     assert_eq!(eval(code).unwrap(), Value::Ref(RefId::from_u32(2)))
 }
+
+#[test]
+fn with_dotter_identity() {
+    let code = r#"
+        withDotter \d -> d
+    "#;
+    assert_eq!(eval(code).unwrap(), Value::Ref(RefId::from_u32(0)))
+}