rust/analytics.md

file name change

change module system and use clauses.

This means we would not change all possiable places for now.(I think this is hard to implement even in future.)

module system

physical module and logic module

each file and folder(lib.rs in the folder) is a physical module.

use and pub could import and export module as logic.

logic module could be seen as namespace.

Only logic module matters.

module tree

module declaration

logic module could be defined in its ancestor's folder.

module

use clauses