old_contents: // just a simple logging library
  // set DEBUG to a non-empty string to see logging
  
  'use strict';
  
  const metadata = require('../package.json');
  
  if (process.env.DEBUG) {
    log(`starting v${metadata.version} at ${new Date()}`);
  }
  
  function log() {
    if (process.env.DEBUG) {
      const logMessages = [`${metadata.name}:`].concat([].slice.call(arguments));
      console.log.apply(console, logMessages);
    }
  }
  
  module.exports = log;
  
new_contents: // just a simple logging library
  // set DEBUG to a non-empty string to see logging
  
  'use strict';
  
  const metadata = require('../package.json');
  
  let log;
  
  if (process.env.DEBUG) {
    log = () => {
      if (process.env.DEBUG) {
        const logMessages = [`${metadata.name}:`].concat([].slice.call(arguments));
        console.log.apply(console, logMessages);
      }
    };
  } else {
    log = () => {};
  }
  
  log(`starting v${metadata.version} at ${new Date()}`);
  
  module.exports = log;
  
subject: use noop function when not logging