weave and weaveWith (#465)

Added weave and weaveWith from tidal

packages/core/euclid.mjs

@@ -11,15 +11,9 @@ This program is free software: you can redistribute it and/or modify it under th
 */
 
 import { Pattern, timeCat, register, silence } from './pattern.mjs';
-import { rotate, flatten } from './util.mjs';
+import { rotate, flatten, splitAt, zipWith } from './util.mjs';
 import Fraction from './fraction.mjs';
 
-const splitAt = function (index, value) {
-  return [value.slice(0, index), value.slice(index)];
-};
-
-const zipWith = (f, xs, ys) => xs.map((n, i) => f(n, ys[i]));
-
 const left = function (n, x) {
   const [ons, offs] = n;
   const [xs, ys] = x;

packages/core/pattern.mjs

@@ -977,7 +977,7 @@ export class Pattern {
 }
 
 //////////////////////////////////////////////////////////////////////
-// functions relating to chords/patterns of lists
+// functions relating to chords/patterns of lists/lists of patterns
 
 // returns Array<Hap[]> where each list of haps satisfies eq
 function groupHapsBy(eq, haps) {
@@ -1026,6 +1026,35 @@ addToPrototype('arp', function (pat) {
   return this.arpWith((haps) => pat.fmap((i) => haps[i % haps.length]));
 });
 
+/**
+ * Takes a time duration followed by one or more patterns, and shifts the given patterns in time, so they are
+ * distributed equally over the given time duration. They are then combined with the pattern 'weave' is called on, after it has been stretched out (i.e. slowed down by) the time duration.
+ * @name weave
+ * @memberof Pattern
+ * @example pan(saw).weave(4, s("bd(3,8)"), s("~ sd"))
+ * @example n("0 1 2 3 4 5 6 7").weave(8, s("bd(3,8)"), s("~ sd"))
+ */
+
+addToPrototype('weave', function (t, ...pats) {
+  return this.weaveWith(t, ...pats.map((x) => set.out(x)));
+});
+
+/**
+ * Like 'weave', but accepts functions rather than patterns, which are applied to the pattern.
+ * @name weaveWith
+ * @memberof Pattern
+ */
+
+addToPrototype('weaveWith', function (t, ...funcs) {
+  const pat = this;
+  const l = funcs.length;
+  t = Fraction(t);
+  if (l == 0) {
+    return silence;
+  }
+  return stack(...funcs.map((func, i) => pat.inside(t, func).early(Fraction(i).div(l))))._slow(t);
+});
+
 //////////////////////////////////////////////////////////////////////
 // compose matrix functions
 

packages/core/test/pattern.test.mjs

@@ -981,4 +981,9 @@ describe('Pattern', () => {
       //      sameFirst(s('bd').apply(set.squeeze.n(3).fast(2)), s('bd').set.squeeze.n(3).fast(2));
     });
   });
+  describe('weave', () => {
+    it('Can distribute patterns along a pattern', () => {
+      sameFirst(n(0, 1).weave(2, s('bd', silence), s(silence, 'sd')), sequence(s('bd').n(0), s('sd').n(1)));
+    });
+  });
 });

packages/core/util.mjs

@@ -206,3 +206,9 @@ export function parseFractional(numOrString) {
 }
 
 export const fractionalArgs = (fn) => mapArgs(fn, parseFractional);
+
+export const splitAt = function (index, value) {
+  return [value.slice(0, index), value.slice(index)];
+};
+
+export const zipWith = (f, xs, ys) => xs.map((n, i) => f(n, ys[i]));

test/__snapshots__/examples.test.mjs.snap

@@ -4231,6 +4231,48 @@ exports[`runs examples > example "vowel" example index 0 1`] = `
 ]
 `;
 
+exports[`runs examples > example "weave" example index 0 1`] = `
+[
+  "[ 0/1 → 1/8 | pan:0.015625 s:bd ]",
+  "[ 3/8 → 1/2 | pan:0.109375 s:bd ]",
+  "[ 3/4 → 7/8 | pan:0.203125 s:bd ]",
+  "[ 1/1 → 9/8 | pan:0.265625 s:bd ]",
+  "[ 11/8 → 3/2 | pan:0.359375 s:bd ]",
+  "[ 7/4 → 15/8 | pan:0.453125 s:bd ]",
+  "[ 2/1 → 17/8 | pan:0.515625 s:bd ]",
+  "[ 19/8 → 5/2 | pan:0.609375 s:bd ]",
+  "[ 11/4 → 23/8 | pan:0.703125 s:bd ]",
+  "[ 3/1 → 25/8 | pan:0.765625 s:bd ]",
+  "[ 27/8 → 7/2 | pan:0.859375 s:bd ]",
+  "[ 15/4 → 31/8 | pan:0.953125 s:bd ]",
+  "[ 1/2 → 1/1 | pan:0.6875 s:sd ]",
+  "[ 3/2 → 2/1 | pan:0.9375 s:sd ]",
+  "[ 5/2 → 3/1 | pan:0.1875 s:sd ]",
+  "[ 7/2 → 4/1 | pan:0.4375 s:sd ]",
+]
+`;
+
+exports[`runs examples > example "weave" example index 1 1`] = `
+[
+  "[ 0/1 → 1/8 | n:0 s:bd ]",
+  "[ 3/8 → 1/2 | n:0 s:bd ]",
+  "[ 3/4 → 7/8 | n:0 s:bd ]",
+  "[ 1/1 → 9/8 | n:1 s:bd ]",
+  "[ 11/8 → 3/2 | n:1 s:bd ]",
+  "[ 7/4 → 15/8 | n:1 s:bd ]",
+  "[ 2/1 → 17/8 | n:2 s:bd ]",
+  "[ 19/8 → 5/2 | n:2 s:bd ]",
+  "[ 11/4 → 23/8 | n:2 s:bd ]",
+  "[ 3/1 → 25/8 | n:3 s:bd ]",
+  "[ 27/8 → 7/2 | n:3 s:bd ]",
+  "[ 15/4 → 31/8 | n:3 s:bd ]",
+  "[ 1/2 → 1/1 | n:4 s:sd ]",
+  "[ 3/2 → 2/1 | n:5 s:sd ]",
+  "[ 5/2 → 3/1 | n:6 s:sd ]",
+  "[ 7/2 → 4/1 | n:7 s:sd ]",
+]
+`;
+
 exports[`runs examples > example "webdirt" example index 0 1`] = `
 [
   "[ 0/1 → 1/8 | s:bd n:0 ]",