strudel/docs/dist/parse.js
Felix Roos f2acc12174 build
2022-02-13 21:48:51 +01:00

141 lines
4.1 KiB
JavaScript

import * as krill from "../_snowpack/link/repl/krill-parser.js";
import * as strudel from "../_snowpack/link/strudel.js";
import {Scale, Note, Interval} from "../_snowpack/pkg/@tonaljs/tonal.js";
import "./tone.js";
import "./midi.js";
import "./voicings.js";
import "./tonal.js";
import "./groove.js";
import * as toneStuff from "./tone.js";
import shapeshifter from "./shapeshifter.js";
const {
pure,
stack,
slowcat,
fastcat,
cat,
sequence,
polymeter,
pm,
polyrhythm,
pr,
silence,
timeCat,
Fraction,
Pattern,
TimeSpan,
Hap
} = strudel;
const {autofilter, filter, gain} = toneStuff;
function reify(thing) {
if (thing?.constructor?.name === "Pattern") {
return thing;
}
return pure(thing);
}
function minify(thing) {
if (typeof thing === "string") {
return mini(thing);
}
return reify(thing);
}
const applyOptions = (parent) => (pat, i) => {
const ast = parent.source_[i];
const options = ast.options_;
const operator = options?.operator;
if (operator) {
switch (operator.type_) {
case "stretch":
const speed = new Fraction(operator.arguments_.amount).inverse().valueOf();
return reify(pat).fast(speed);
}
console.warn(`operator "${operator.type_}" not implemented`);
}
if (options?.weight) {
return pat;
}
const unimplemented = Object.keys(options || {}).filter((key) => key !== "operator");
if (unimplemented.length) {
console.warn(`option${unimplemented.length > 1 ? "s" : ""} ${unimplemented.map((o) => `"${o}"`).join(", ")} not implemented`);
}
return pat;
};
export function patternifyAST(ast) {
switch (ast.type_) {
case "pattern":
const children = ast.source_.map(patternifyAST).map(applyOptions(ast));
if (ast.arguments_.alignment === "v") {
return stack(...children);
}
const weightedChildren = ast.source_.some((child) => !!child.options_?.weight);
if (weightedChildren) {
return timeCat(...ast.source_.map((child, i) => [child.options_?.weight || 1, children[i]]));
}
return sequence(...children);
case "element":
if (ast.source_ === "~") {
return silence;
}
if (typeof ast.source_ !== "object") {
return ast.source_;
}
return patternifyAST(ast.source_);
case "stretch":
return patternifyAST(ast.source_).slow(ast.arguments_.amount);
case "scale":
let [tonic, scale] = Scale.tokenize(ast.arguments_.scale);
const intervals = Scale.get(scale).intervals;
const pattern = patternifyAST(ast.source_);
tonic = tonic || "C4";
console.log("tonic", tonic);
return pattern.fmap((step) => {
step = Number(step);
if (isNaN(step)) {
console.warn(`scale step "${step}" not a number`);
return step;
}
const octaves = Math.floor(step / intervals.length);
const mod = (n, m2) => n < 0 ? mod(n + m2, m2) : n % m2;
const index = mod(step, intervals.length);
const interval = Interval.add(intervals[index], Interval.fromSemitones(octaves * 12));
return Note.transpose(tonic, interval || "1P");
});
default:
console.warn(`node type "${ast.type_}" not implemented -> returning silence`);
return silence;
}
}
export const mini = (...strings) => {
const pattern = sequence(...strings.map((str) => {
const ast = krill.parse(`"${str}"`);
return patternifyAST(ast);
}));
return pattern;
};
const m = mini;
const s = (...strings) => {
const patternified = strings.map((s2) => minify(s2));
return stack(...patternified);
};
export const h = (string) => {
const ast = krill.parse(string);
return patternifyAST(ast);
};
export const parse = (code) => {
let _pattern;
let mode;
try {
_pattern = h(code);
mode = "pegjs";
} catch (err) {
mode = "javascript";
code = shapeshifter(code);
_pattern = eval(code);
if (_pattern?.constructor?.name !== "Pattern") {
const message = `got "${typeof _pattern}" instead of pattern`;
throw new Error(message + (typeof _pattern === "function" ? ", did you forget to call a function?" : "."));
}
}
return {mode, pattern: _pattern};
};