// zip two arrays
export function zip(a, b) {
  return a.map((k, i) => [k, b[i]]);
}

export function capitalizeFirstLetter(val) {
  return String(val).charAt(0).toUpperCase() + String(val).slice(1);
}

export const memoize = callback => {
  let called = false
  let result;
  return () => {
    if (!called) {
      result = callback();
      called = true;
    }
    return result;
  };
};

export const indent = (multiline, n) => {
  return multiline.split('\n').map(line => ' '.repeat(n)+line).join('\n');
}