src/evaluator/extensions.js
function initialize(shell) {
  shell.loadedExtensions = {};

  shell.registerCommand('extension', extensionCommand);
  shell.registerCommand('extensions', extensionsCommand);
}
function initialize(shell) {
  shell.loadedExtensions = {};

  shell.registerCommand('extension', extensionCommand);
  shell.registerCommand('extensions', extensionsCommand);
}
Initializes the shell with extensions related functionality.