- transpiler now always returns an object

- emit transpiler metadata from evaluate / afterEval
- currently logging miniLocations from Repl.jsx

packages/core/evaluate.mjs

@@ -37,8 +37,12 @@ function safeEval(str, options = {}) {
 }
 
 export const evaluate = async (code, transpiler) => {
+  let meta = {};
   if (transpiler) {
-    code = transpiler(code); // transform syntactically correct js code to semantically usable code
+    // transform syntactically correct js code to semantically usable code
+    const transpiled = transpiler(code);
+    code = transpiled.output;
+    meta = transpiled;
   }
   // if no transpiler is given, we expect a single instruction (!wrapExpression)
   const options = { wrapExpression: !!transpiler };
@@ -48,5 +52,5 @@ export const evaluate = async (code, transpiler) => {
     const message = `got "${typeof evaluated}" instead of pattern`;
     throw new Error(message + (typeof evaluated === 'function' ? ', did you forget to call a function?' : '.'));
   }
-  return { mode: 'javascript', pattern: evaluated };
+  return { mode: 'javascript', pattern: evaluated, meta };
 };

packages/core/repl.mjs

@@ -35,11 +35,10 @@ export function repl({
     }
     try {
       await beforeEval?.({ code });
-      let { pattern } = await _evaluate(code, transpiler);
-
+      let { pattern, meta } = await _evaluate(code, transpiler);
       logger(`[eval] code updated`);
       setPattern(pattern, autostart);
-      afterEval?.({ code, pattern });
+      afterEval?.({ code, pattern, meta });
       return pattern;
     } catch (err) {
       // console.warn(`[repl] eval error: ${err.message}`);