Dart Programming Language
Dart is a new scalable web programming language, with tools and libraries, for structured web app engineering, developed by Google. Dart is intended to address JavaScript's problems and ultimately replace JavaScript as the lingua franca of web development on the open web platform. The goal of Dart is to provide better performance, with the ability "to be more easily tooled for large-scale projects" and better security features.

Free Dart Editor
Dart Editor is an open-source tool for editing, debugging, and running Dart applications. Dart Editor helps you write web apps with Dart web programming language. The editor and language are part of the open-source Dart project, which also includes libraries, a new virtual machine, a package manager, and more. Dart compiles to JavaScript to run across the modern web. It is well-suited to modern app development and capable of high-performance implementations. In addition to editing Dart programs, you can use Dart Editor to invoke the Dart-to-JavaScript compiler and launch Dart-based web apps.

Download free Dart Editor for Windows 64-bit and Windows 32-bit.
Download free Dart Editor for Linux 64-bit and Linux 32-bit. 
Download free Dart Editor for Mac OS X.
Dart Editor file size 158MB.
Dart Editor Website

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