big commit

static/js/components/literate-programming/eval.js

@@ -1,8 +1,21 @@
 let outputIndex = 0;
 
-export function getOutputIndex() {
-    return outputIndex;
-}
+export const jsConsole = console;
+
+// Overwrite globalThis.console with domConsole to redirect output to the DOM console.
+// To always output to the JavaScript console regardless, use jsConsole.
+export const domConsole = {
+    log(...message) {
+        postMessage({
+            kind: "output",
+            output: {
+                kind: "console.log",
+                message: [...message],
+            },
+            outputIndex,
+        });
+    }
+};
 
 async function withTemporaryGlobalScope(callback) {
     let state = {
@@ -13,6 +26,7 @@ async function withTemporaryGlobalScope(callback) {
         }
     };
     await callback(state);
+    jsConsole.trace(state.oldValues, "bringing back old state");
     for (let key in state.oldValues) {
         globalThis[key] = state.oldValues[key];
     }
@@ -20,15 +34,11 @@ async function withTemporaryGlobalScope(callback) {
 
 let evaluationComplete = null;
 
-export async function evaluate(commands, { start, success, error }) {
+export async function evaluate(commands, { error, newOutput }) {
     if (evaluationComplete != null) {
         await evaluationComplete;
     }
 
-    if (start != null) {
-        start();
-    }
-
     let signalEvaluationComplete;
     evaluationComplete = new Promise((resolve, _reject) => {
         signalEvaluationComplete = resolve;
@@ -36,21 +46,19 @@ export async function evaluate(commands, { start, success, error }) {
 
     outputIndex = 0;
     try {
-        await withTemporaryGlobalScope(async scope => {
-            for (let command of commands) {
-                if (command.kind == "module") {
-                    let blobUrl = URL.createObjectURL(new Blob([command.source], { type: "text/javascript" }));
-                    let module = await import(blobUrl);
-                    for (let exportedKey in module) {
-                        scope.set(exportedKey, module[exportedKey]);
-                    }
-                } else if (command.kind == "output") {
-                    ++outputIndex;
+        for (let command of commands) {
+            if (command.kind == "module") {
+                let blobUrl = URL.createObjectURL(new Blob([command.source], { type: "text/javascript" }));
+                let module = await import(blobUrl);
+                for (let exportedKey in module) {
+                    globalThis[exportedKey] = module[exportedKey];
                 }
+            } else if (command.kind == "output") {
+                if (newOutput != null) {
+                    newOutput(outputIndex);
+                }
+                ++outputIndex;
             }
-        });
-        if (success != null) {
-            success();
         }
         postMessage({
             kind: "evalComplete",