Feature: Language Server Protocol, Definition support #676

Created by: Efratror

Description

Since there now is LSP support for processing, it would be nice if the server would be able to "find declarations"

Expected Behavior

Finding declarations is supported in the PDE, so it should also be available for the LS

Current Behavior

Finding declarations isn't supported at the moment

Your Environment

• Processing version: 4.2
• Operating System and OS version: Windows 10

Possible Causes / Solutions

• Add a declarationFinder class to the LSP folder
• Use it to find a declaration using the AST from the preprocessor (Use "InspectMode" as an example)
• Send (found) the declaration back to a LS-client

I'm willing to implement this, so a PR is in the making