Testing out approach to allow list patterns in partials

packages/core/pattern.mjs

@@ -3624,3 +3624,54 @@ for (const name of distAlgoNames) {
     return this.distort(argsPat);
   };
 }
+
+/**
+ * Turns a list of patterns into a single pattern which outputs list-values
+ *
+ * @name parray
+ * @returns Pattern
+ */
+export const parray = (pats) => {
+  const pack = (...xs) => xs;
+  let acc = pure(curry(pack, null, pats.length));
+  for (const p of pats) acc = acc.appBoth(reify(p));
+  return acc;
+};
+
+/**
+ * Scale the magnitude of the harmonics of one of the core synths ('sine', 'tri', 'saw', ..)
+ *
+ * Can also be used to create a new synth via `s('user').partials(...)`
+ *
+ * @name partials
+ * @param {number[] | Pattern} partials List of [0, 1] magnitudes for partials. 0th entry is the first harmonic (i.e. DC offset is skipped)
+ * @example
+ * s("user").seg(16).n(irand(8)).scale("A:major")
+ *   .partials([1, 0, 1, 0, 0, 1])
+ * @example
+ * s("saw").seg(8).n(irand(12)).scale("G#:minor")
+ *   .partials(binaryL(256))
+ */
+export const { partials } = register('partials', (list, pat) => {
+  if (Array.isArray(list)) {
+    list = parray(list);
+  }
+  return pat.withValue((v) => ({...v, partials: list}));
+});
+
+/**
+ * Rotates the harmonics of one of the core synths ('sine', 'tri', 'saw', 'user', ..) by a list of phases
+ *
+ * @name phases
+ * @param {number[] | Pattern} phases List of [0, 1) phases for partials. 0th entry is the first phase (i.e. DC offset is skipped)
+ * @example
+ * s("saw").seg(8).n(irand(12)).scale("G#:minor")
+ *   .partials(binaryL(256))
+ *   .phases(randL(20))
+ */
+export const { phases } = register('phases', (list, pat) => {
+  if (Array.isArray(list)) {
+    list = parray(list);
+  }
+  return pat.withValue((v) => ({...v, phases: list}));
+});