comments on debug context

src/debug.ts

@@ -4,6 +4,7 @@ import async_hooks from 'async_hooks';
 const debugInstances: {[namespace: string]: {[postfix: string]: Debugger}} = {};
 const asyncContext = new Map();
 
+// any child async calls/promises will inherit the asyncContex from their parent (triggerAsyncId)
 async_hooks.createHook({
   init(asyncId, type, triggerAsyncId, resource) {
     if (asyncContext.has(triggerAsyncId)) {
@@ -17,8 +18,10 @@ async_hooks.createHook({
 
 export function withDebugContext<F extends (...args: any[]) => any>(postfix: string, fn: F) {
   return async (...args: Parameters<F>): Promise<Awaited<ReturnType<F>>> => {
+    // associates the promise created by this function with the postfix to be added to the debug namespace
     const asyncId = async_hooks.executionAsyncId();
     asyncContext.set(asyncId, postfix);
+
     try {
       return await fn(...args);
     } finally {
@@ -33,8 +36,10 @@ function getContext() {
 }
 
 export function Debug(namespace: string) {
+  // debug instances are organized by postfix to the namespace (default is no postfix)
   debugInstances[namespace] = {'': debug(namespace)};
   return function(...args: Parameters<Debugger>) {
+    // getContext gives the postfix to the namespace (create new debug instance if we don't have one yet)
     if (!debugInstances[namespace][getContext() ?? '']) {
       debugInstances[namespace][getContext()] = debug(namespace + getContext());
     }