尾声优化在Babel ES2015中不起作用

Question

Just implemented the tail calls sample code in Node.js which will be translated by using babel (enabled the ES2015 Syntax support), but it just throws the exception Maximum call stack size exceeded .

//index.js
require('babel-core/register');
require('./sample.js');

//sample.js
function factorial(n, acc = 1) {
    'use strict';
    if (n <= 1) return acc;
    return factorial(n - 1, n * acc);
}

// Stack overflow in most implementations today,
// // but safe on arbitrary inputs in ES6
factorial(100000)

Here is my babel depens.

├─┬ babel-core@6.2.1
│ ├─┬ babel-code-frame@6.1.18
│ │ ├─┬ chalk@1.1.1
│ │ │ ├── ansi-styles@2.1.0
│ │ │ ├── escape-string-regexp@1.0.3
│ │ │ ├─┬ has-ansi@2.0.0
│ │ │ │ └── ansi-regex@2.0.0
│ │ │ ├── strip-ansi@3.0.0
│ │ │ └── supports-color@2.0.0
│ │ ├── esutils@2.0.2
│ │ ├── js-tokens@1.0.2
│ │ ├─┬ line-numbers@0.2.0
│ │ │ └── left-pad@0.0.3
│ │ └─┬ repeating@1.1.3
│ │   └─┬ is-finite@1.0.1
│ │     └── number-is-nan@1.0.0
│ ├─┬ babel-generator@6.2.0
│ │ ├─┬ detect-indent@3.0.1
│ │ │ ├── get-stdin@4.0.1
│ │ │ └── minimist@1.2.0
│ │ ├── is-integer@1.0.6
│ │ └── trim-right@1.0.1
│ ├── babel-helpers@6.1.20
│ ├── babel-messages@6.2.1
│ ├─┬ babel-register@6.2.0
│ │ ├── core-js@1.2.6
│ │ ├─┬ home-or-tmp@1.0.0
│ │ │ ├── os-tmpdir@1.0.1
│ │ │ └── user-home@1.1.1
│ │ └─┬ source-map-support@0.2.10
│ │   └─┬ source-map@0.1.32
│ │     └── amdefine@1.0.0
│ ├── babel-runtime@5.8.34
│ ├── babel-template@6.2.0
│ ├─┬ babel-traverse@6.2.0
│ │ ├── globals@8.12.1
│ │ └─┬ invariant@2.2.0
│ │   └── loose-envify@1.1.0
│ ├─┬ babel-types@6.2.0
│ │ └── to-fast-properties@1.0.1
│ ├── babylon@6.2.0
│ ├── convert-source-map@1.1.2
│ ├─┬ debug@2.2.0
│ │ └── ms@0.7.1
│ ├── json5@0.4.0
│ ├── lodash@3.10.1
│ ├─┬ minimatch@2.0.10
│ │ └─┬ brace-expansion@1.1.1
│ │   ├── balanced-match@0.2.1
│ │   └── concat-map@0.0.1
│ ├── path-exists@1.0.0
│ ├── path-is-absolute@1.0.0
│ ├── private@0.1.6
│ ├── shebang-regex@1.0.0
│ ├── slash@1.0.0
│ └── source-map@0.5.3
└─┬ babel-preset-es2015@6.1.18
  ├── babel-plugin-check-es2015-constants@6.2.0
  ├── babel-plugin-transform-es2015-arrow-functions@6.1.18
  ├── babel-plugin-transform-es2015-block-scoped-functions@6.1.18
  ├── babel-plugin-transform-es2015-block-scoping@6.1.18
  ├─┬ babel-plugin-transform-es2015-classes@6.2.2
  │ ├── babel-helper-define-map@6.2.0
  │ ├── babel-helper-function-name@6.2.0
  │ ├── babel-helper-optimise-call-expression@6.1.18
  │ └── babel-helper-replace-supers@6.2.0
  ├── babel-plugin-transform-es2015-computed-properties@6.1.18
  ├── babel-plugin-transform-es2015-destructuring@6.1.18
  ├── babel-plugin-transform-es2015-for-of@6.1.18
  ├── babel-plugin-transform-es2015-function-name@6.1.18
  ├── babel-plugin-transform-es2015-literals@6.1.18
  ├─┬ babel-plugin-transform-es2015-modules-commonjs@6.2.0
  │ └── babel-plugin-transform-strict-mode@6.2.0
  ├── babel-plugin-transform-es2015-object-super@6.1.18
  ├─┬ babel-plugin-transform-es2015-parameters@6.1.18
  │ ├─┬ babel-helper-call-delegate@6.2.0
  │ │ └── babel-helper-hoist-variables@6.1.18
  │ └── babel-helper-get-function-arity@6.2.0
  ├── babel-plugin-transform-es2015-shorthand-properties@6.1.18
  ├── babel-plugin-transform-es2015-spread@6.1.18
  ├─┬ babel-plugin-transform-es2015-sticky-regex@6.1.18
  │ └── babel-helper-regex@6.1.18
  ├── babel-plugin-transform-es2015-template-literals@6.1.18
  ├── babel-plugin-transform-es2015-typeof-symbol@6.1.18

And one thing to prove I setup up my environment correctly is, the default parameter in a function did work in my babel project, but not in a pure nodejs environment. For example,

function  add(a, b=2) {
    console.log(a + b);
}
add(3); //In babel project this will output 5
//But it just threw an exception in pure nodejs file.(without require babel/register and setup the es2015 subset in .babelrc)

Here is my entry files.

However, if I try to implement other feature,such as template string or arrows function, they are all working correctly. Any ideas?

Answer 1

There is no environment yet that supports TCO. Babel used have an experimental TCO transform, but it was removed in v6.