https://github.com/thlorenz/v8-flags

Configures v8 flags at runtime.
https://github.com/thlorenz/v8-flags

Last synced: about 2 months ago
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Configures v8 flags at runtime.

• Host: GitHub
• URL: https://github.com/thlorenz/v8-flags
• Owner: thlorenz
• License: mit
• Created: 2014-06-25T17:20:15.000Z (over 10 years ago)
• Default Branch: master
• Last Pushed: 2015-04-10T00:53:35.000Z (over 9 years ago)
• Last Synced: 2024-10-23T06:16:47.361Z (2 months ago)
• Language: C
• Homepage:
• Size: 667 KB
• Stars: 118
• Watchers: 9
• Forks: 13
• Open Issues: 3
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
# v8-flags [![build status](https://secure.travis-ci.org/thlorenz/v8-flags.png)](http://travis-ci.org/thlorenz/v8-flags)

Configures v8 flags at runtime.

```js

// use-strict-violator.js

a = "I'm the trouble starter, punking instigator"

module.exports = a;

```

```js

var flags = require('v8-flags').flags;

console.log('inital use strict', flags.use_strict());

flags.use_strict(true);

console.log('set use strict to', flags.use_strict());

try {

  require('./use-strict-violator');

} catch(err) {

  console.error('FAIL:', err);

}

flags.use_strict(false);

console.log('set use strict to', flags.use_strict());

var violator = require('./use-strict-violator');

console.log(violator)

```

```

inital use strict false

set use strict to true

FAIL: [ReferenceError: a is not defined]

set use strict to false

I'm the trouble starter, punking instigator

```

## Installation

    npm install v8-flags

## Contributions

I am doing my best to document each flag, but am hoping for others *especially the ones with insider knowledge* to supply useful comments.

I made this as easy as possible, all you have to do is add/edit the `.md` file with the name of the flag in [this

folder](https://github.com/thlorenz/v8-flags/tree/master/scripts/comments) and run `npm run flag-doc` to

update all documentation with the added details.

## API

The different versions of v8 and thus Node.js have different flags and therefore the API fluctuates somewhat between the

versions. The API is generated on install to match the Node.js version you are using.

The flags for the *currently* latest Node.js versions `0.8`, `0.10` and `0.11` are documented in the following

locations:

- [0.8](https://github.com/thlorenz/v8-flags/blob/master/flags-0.8.md)

- [0.10](https://github.com/thlorenz/v8-flags/blob/master/flags-0.10.md)

- [0.11](https://github.com/thlorenz/v8-flags/blob/master/flags-0.11.md)

The below API allows to access and configure these flags.

**Table of Contents**  *generated with [DocToc](http://doctoc.herokuapp.com/)*

- [enforceFlagImplications()](#enforceflagimplications)

- [flags()](#flags)

  - [Example](#example)

- [listFlags() → {Object}](#listflags--object)

- [meta() → {Array.}](#meta--arrayobject)

- [printHelp()](#printhelp)

- [resetAllFlags()](#resetallflags)



















enforceFlagImplications()









Enforces all flag implications.





Source:





index.js

, 

lineno 117













flags()









Exposes methods to get and set v8 flags.

Example

var flags = require('v8-flags').flags;

console.log(flags.use_strict()); // false

flags.use_strict(true)

console.log(flags.use_strict()); // true





Source:





index.js

, 

lineno 21













listFlags() → {Object}









Lists all flags along with their current value.





Source:





index.js

, 

lineno 85







Returns:



key/value pair for each flag







Type





Object











meta() → {Array.<Object>}









The meta data for the flags.

It is initialized on startup from the definitions found in C++ land.





Source:





index.js

, 

lineno 39







Returns:



array of objects with the folloing properties each





name: flag name



default: default setting of the flag



type: type of the flag



description: the description of the flag



readonly: set true if flag cannot be set



configurable: set true if setting the flag at runtime has the desired effect



implications: flags that will be set to true whenever this flag is true and enforceFlagImplications is called



negativeImplications: flags that will be set to false whenever this flag is false and enforceFlagImplications is called









Type





Array.<Object>











printHelp()









Prints flag help to the console.





Source:





index.js

, 

lineno 100













resetAllFlags()









Resets all flags to their default values





Source:





index.js

, 

lineno 108













*generated with [docme](https://github.com/thlorenz/docme)*



## License

MIT