Generating and managing the translations files for large scale applications like ERP etc is very cumbersome.

# 🚀 feature request.
Generating and managing the translations files for large scale applications like ERP etc is very cumbersome.

### Relevant Package

This feature request is for @angular/....

### Description
Using the angular's builtin translation which the angular platform provides, managing and generating the translation files for multiple locale is very cumbersome , error prone and very difficult to manage as the application size scales, as generating the translation files after adding new i18n tags , generates the a default file *messages.xlf* and it becomes very difficult to dig into this default file (because of size .. lines of code.) and parse out the new trans-units and then move them to each locale files manually , and paste the target tag for the new trans-units .

### Describe the solution you'd like
Either the translation file should be provided for each module or component level, or there must be some version control system used to check the differences/changes in the default messages.xlf file and these changes automatically being added to other locale files . Means atleast the new trans-units must be appended automatically to the locale files that the intended developer needs to create.

### Describe alternatives you've considered
We have gone through ngx-Translate etc tools that provides run-time translation using pipes, but if the angular's builtin internalization module provides additional updates in near future to ease the internationalization process for developers , its far better than other third party packages.

首先查看生成 messages.xlf 的 Angular CLI 国际化工作流，以及提到的 ngx-Translate 替代方案。明确模块级或组件级文件相对于自动 locale 更新的预期范围；完成标准应包括指定一种可维护的方式，用于在各 locale 文件之间生成或同步新的 trans-units。

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