add beforeStart callback

packages/core/cyclist.mjs

@@ -8,8 +8,19 @@ import createClock from './zyklus.mjs';
 import { logger } from './logger.mjs';
 
 export class Cyclist {
-  constructor({ interval, onTrigger, onToggle, onError, getTime, latency = 0.1, setInterval, clearInterval }) {
+  constructor({
+    interval,
+    onTrigger,
+    onToggle,
+    onError,
+    getTime,
+    latency = 0.1,
+    setInterval,
+    clearInterval,
+    beforeStart,
+  }) {
     this.started = false;
+    this.beforeStart = beforeStart;
     this.cps = 0.5;
     this.num_ticks_since_cps_change = 0;
     this.lastTick = 0; // absolute time when last tick (clock callback) happened
@@ -82,7 +93,8 @@ export class Cyclist {
     this.started = v;
     this.onToggle?.(v);
   }
-  start() {
+  async start() {
+    await this.beforeStart?.();
     this.num_ticks_since_cps_change = 0;
     this.num_cycles_at_cps_change = 0;
     if (!this.pattern) {
@@ -103,10 +115,10 @@ export class Cyclist {
     this.lastEnd = 0;
     this.setStarted(false);
   }
-  setPattern(pat, autostart = false) {
+  async setPattern(pat, autostart = false) {
     this.pattern = pat;
     if (autostart && !this.started) {
-      this.start();
+      await this.start();
     }
   }
   setCps(cps = 0.5) {

packages/core/repl.mjs

@@ -10,6 +10,7 @@ export function repl({
   defaultOutput,
   onEvalError,
   beforeEval,
+  beforeStart,
   afterEval,
   getTime,
   transpiler,
@@ -53,6 +54,7 @@ export function repl({
     },
     setInterval,
     clearInterval,
+    beforeStart,
   };
 
   // NeoCyclist uses a shared worker to communicate between instances, which is not supported on mobile chrome
@@ -69,9 +71,9 @@ export function repl({
     return silence;
   };
 
-  const setPattern = (pattern, autostart = true) => {
+  const setPattern = async (pattern, autostart = true) => {
     pattern = editPattern?.(pattern) || pattern;
-    scheduler.setPattern(pattern, autostart);
+    await scheduler.setPattern(pattern, autostart);
   };
   setTime(() => scheduler.now()); // TODO: refactor?
 
@@ -159,7 +161,7 @@ export function repl({
         throw new Error(message + (typeof evaluated === 'function' ? ', did you forget to call a function?' : '.'));
       }
       logger(`[eval] code updated`);
-      setPattern(pattern, autostart);
+      await setPattern(pattern, autostart);
       updateState({
         miniLocations: meta?.miniLocations || [],
         widgets: meta?.widgets || [],