@gerhobbelt/mathjax-third-party-extensions/legacy/siunitx/node_modules/underscore.string/map.js

A list of MathJax extensions provided by third-party contributors

var makeString = require('./helper/makeString');

module.exports = function(str, callback) {
  str = makeString(str);

  if (str.length === 0 || typeof callback !== 'function') return str;

  return str.replace(/./g, callback);
};