add xen package

packages/xen/package.json

@@ -0,0 +1,26 @@
+{
+  "name": "@strudel/xen",
+  "version": "0.0.1",
+  "description": "Xenharmonic API for strudel",
+  "main": "xen.mjs",
+  "scripts": {
+    "test": "mocha --colors"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/tidalcycles/strudel.git"
+  },
+  "keywords": [
+    "tidalcycles",
+    "strudel",
+    "pattern",
+    "livecoding",
+    "algorave"
+  ],
+  "author": "Felix Roos <flix91@gmail.com>",
+  "license": "GPL-3.0-or-later",
+  "bugs": {
+    "url": "https://github.com/tidalcycles/strudel/issues"
+  },
+  "homepage": "https://github.com/tidalcycles/strudel#readme"
+}

packages/xen/test/xen.test.mjs

@@ -0,0 +1,8 @@
+import { strict as assert } from 'assert';
+import { edo } from '../xen.mjs';
+
+describe('xen', () => {
+  it('edo', () => {
+    assert.deepStrictEqual(edo('3edo'), [1, Math.pow(2, 1 / 3), Math.pow(2, 2 / 3)]);
+  });
+});

packages/xen/xen.mjs

@@ -1,7 +1,7 @@
 import { Pattern } from '@strudel/core/strudel.mjs';
 import { mod } from '../../packages/core/util.mjs';
 
-function edo(name) {
+export function edo(name) {
   if (!/^[1-9]+[0-9]*edo$/.test(name)) {
     throw new Error('not an edo scale: "' + name + '"');
   }