feat: added Tune scales to Xen, improved documentation re uzu/strudel#1944

packages/xen/xen.mjs

@@ -5,7 +5,7 @@ This program is free software: you can redistribute it and/or modify it under th
 */
 
 import { register, _mod, parseNumeral, removeUndefineds } from '@strudel/core';
-
+import Tune from './tunejs.js'
 
 // returns a list of frequency ratios for given edo scale
 export function edo(name) {
@@ -30,12 +30,18 @@ const defaultBase = 220;
 
 // Assumes a base of 220. Returns a filtered scale based on 'indices'
 function getXenScale(scale, indices) {
+  let tune = new Tune()
   if (typeof scale === 'string') {
     if (/^[1-9]+[0-9]*edo$/.test(scale)) {
       scale = edo(scale);
     } else if (presets[scale]) {
       scale = presets[scale];
-    } else {
+    } 
+    else if (tune.isValidScale(scale)) {
+      tune.loadScale(scale)
+      scale = tune.scale
+    } 
+    else {
       throw new Error('unknown scale name: "' + scale + '"');
     }
   }
@@ -69,6 +75,7 @@ function xenOffset(xenScale, offset, index = 0) {
  * @param {(string | number[] )} scaleNameOrRatios
  * @tags music_theory
  * @example
+ * // A major tried in 31edo:
  * "0 8 18".xen("31edo").freq().piano()
  * @example
  * // You can also use xen with frequency ratios. 
@@ -78,8 +85,15 @@ function xenOffset(xenScale, offset, index = 0) {
  * Math.pow(2, 8/31),
  * Math.pow(2, 18/31),
  * ]).freq().piano()
+ * @example 
+ * // xen also supports all scale names that 
+ * // tune does:
+ * "0 1 2 3 4 5".xen("hexany15").freq()
+ * // equiv to: 
+ * // "0 1 2 3 4 5".tune("hexany15").mul("220").freq()
  */
 
+// TODO how do you reference another function in jsdoc (tune, above)
 // TODO support tunings defined in './tunejs.js'
 export const xen = register('xen', function (scaleNameOrRatios, pat) {
   return pat.withHaps((haps) => {