Takes a D3/CSS transform string value and decomposes to an object

decompose.js

/**
 * Decomposes transform attribute in an object
 * @param {string} input Transform string to decompose
 * @param {boolean=true} asString Return the values as arrays (false) or transform strings (true)
 * @returns {}
 */
const getTransform = (input, asString = true) => {
  const typeRegex = /(\w+\([\w+., -]*\))/g;
  const valuesRegex = /([-\d.]+)[, ]?/g;

  let transform = {};

  if(!input || input === '') return transform;

  let t = null;

  while (t = typeRegex.exec(input)) {
    const typeValuesRegex = /(\w+)\(([^\)]+)\)/g;
    let tv = typeValuesRegex.exec(t[1]);

    const key = tv[1];
    const valueString = tv[2];
    let values = [];

    let v = null;
    while (v = valuesRegex.exec(valueString)) {
      values.push(v[1]);
    }

    transform[key] = asString === true ? `${key}(${values.join(',')})` : values;
  }

  return transform;
}

/**
 * Example
 */

// Simple
console.dir(getTransform('translate(1, -1.5)'));
// { translate: 'translate(1,-1.5)' }

// Return values as array
console.dir(getTransform('translate(1, -1.5, 3.0002)', false));
// { translate: ['1', '-1.5', '3.0002'] }

console.dir(getTransform('translate(1, -1.5) scale(5)'));
// { translate: 'translate(1,-1.5)', scale: 'scale(5)' }

console.dir(getTransform('translate(1, -1.5) rotate(4) scale(5.5, -0.00542)'));
// { translate: 'translate(1,-1.5)', rotate: 'rotate(4)', scale: 'scale(5.5,-0.00542)' }