This Blockly can be used to build a block environment for a functional language.

Some features of this fork:

• Features custom connector shapes.
• Allows types to be polymorphic.
• Uses Hindley Milner type inference to determine the types of blocks.
• Changes the way local variables work. They can be instantiated by dragging them from the definining block.
• Allows custom using data types to be defined using algabraic data types, using sum and product blocks.
• Some support for first class functions.

A showcase of the this fork can be found at CodeWorld Blocks, which is a visual functional programming environment, which generates CodeWorld programs that are run in the browser. CodeWorld uses Haskell, which is a pure functional programming language, no side-effects allowed !.

This fork uses further changes from the following users:

• awmorph with his Blockly fork which he uses for math expressions, this fork is extends the work from Sorin's fork (below).
• slerner with his Blockly fork that supports better types and polymorphism.

Google's Blockly is a web-based, visual programming editor. Users can drag blocks together to build programs. All code is free and open source.

The project page is https://developers.google.com/blockly/