Abstract

• Breaking Change (possible)
• From some conversation with @azu on Twitter, I tried to convert codes to TypeScript.
• This changeset includes some changes for build system.
• This change only does rewrite codes with TypeScript. To publish d.ts in npm, we need push more patch onto this.

Motivation

• Increase interoperabitily with static typing world like TypeScript or Flowtype.
• Erase some inconsistency of API system of this library by static checking types of them.

Detailed Design

Change build system

This introduces 2-phase build system.

1. At 1st phase, Try type checking under src/ with tsc and emit a plain JS code into /__obj/ temp dir.
   In this phase, this also try to copy all javascript file into /__obj/ to keep the content of /src/.
2. At 2nd phase, Do down-level transform by babel and emit the transformed one into /lib/.

By this change, we can achive to convert our source code to TypeScript incrementally without at giant single patch file.

Unit tese imports from /lib/

By the above change, we need to load the code to test unit tests for incremental converting without changeing
unit tests.

Convert TypeScript

Convert *.js to *.ts simply.

This change escapes from the problem which is that some dependency does not have any d.ts by dirty hacking.

Add *.d.ts and *.js with same name. TypeScript compiler uses *.d.ts to resolve type checking.
But we use *.js file to load a file actually on the runtime. This dirty hack resolves the problem.

Drawback

• Drop JSDoc.
  • By this change, user who uses Closure Compiler advanced optimization might face to some troubles.
• Increase Complexity of build system.

Alternative Approach

• Using Flowtype instead. This is also possible solution.
  But this tries to use TypeScript by conversations with @azu.

Unresolved Items

• Clean up the build system: feat(typescript): add d.ts to pacakge.json #78.
• Fix some inconsistency of APIs: TypeScript: StoreGroup#getState interface #71
• No emit *.d.ts files into /lib/: feat(typescript): add d.ts to pacakge.json #78.
• Disable power-assert temporary: Re-enable power-assert #83
• Remove jsdoc-to-assert properly: TypeScript-Babel: jsdoc-to-assert is not working #82
• No work documentation build by JSDoc:
• No any linting:
• Reduce any type from public APIs:
• Mark Abstract Class/Property as abstract correctly.
• Relax complex dependency.
  • Some types depends with each other complexly.