MetaES Playground

This is a playground for MetaES interpreter. MetaES is a metacircular interpreter of JavaScript language written in JavaScript at EcmaScript 5.1 standard. Learn more about the MetaES project.

Playground allows to run JavaScript in MetaES interpreter and watch live results in its user interface.

Playground is written using Polymer Project and TypeScript. Currently recommended browser is Google Chrome.

Features

Although MetaES Playground is currently in early alpha state, it has a number of features:

• On change evaluation - the code is re-evaluated everytime is changed
• Code completion of variables and members. Press ctrl+space to see completions of variables. Press . after any Identifier to see its members. Highly experimental.

• Error notification - red text below the editor. It can be both syntax error (static) or error from JavaScript execution (dynamic).

• Highlighting of just evaluated code with light green

• Variables list display - variables in currently evaluated scope and all parent scopes

• Callstack display - currently evaluated functions list

• Display current token value below the editor, if evaluated before. Highlight token under the cursor in light blue.

• Output - mimic default window.console.log, but log everything to original console as well

• Canvas - small div element that for visual output

• metaes.evaluate patching - create special metaes object that intercepts call to original metaes.evaluate. It allows playground to see configuration for MetaES and hook its own interceptors. Slows down execution quite significantly.

Installation

Clone the repo and then:

npm install && bower install

Starting dev mode

grunt serve

Browser should be automatically opened at http://localhost:9000/

Building

grunt build

And then the build artifact is located in ./dist.

Types installation

To install types for example for codemirror, type in your cmd:

./node_modules/tsd/build/cli.js query codemirror --action install

Contribute

• You can report issues and bugs.
• Help with implementation of new features using pull requests.

License

The MIT License (MIT)

Copyright (c) 2015 Bartosz Krupa

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.