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Changelog entry (a user-readable short description of the changes that goes to CHANGELOG.md):

• Hide Settings implementation

The idea is that you can include Settings.h to work with a Settings object, without the need to know about its internals, macros or settings declaration. Just declare extern const Settings{Type} name (as we do for ProfileEvents, ErrorCodes, etc) and use the subscript ([]) operator.

Major simplifications would happen in BaseSettings once we remove direct usages.

Good points:

• Setting struct can be much smaller (future)
• Way less dependencies on inner details of settings, which means less build time and less rebuilds to add a setting.

Bad points:

• Need to specify the extern of each setting used in the file. If not done compilation fail, if done incorrectly it will work and it will link but have undefined errors in runtime. This is detected by style check so it should not appear.

Documentation entry for user-facing changes

• Documentation is written (mandatory for new features)

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• Woolen Wolfdog
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