Feature Request - GIT config - Reference value of init.defaultBranch in alias

Hello,

I am curious why it is not possible to reference other variables in git config.

Useful scenario:

Global git config containing all useful aliases which often reference the default main branch. I discovered the config variable init.defaultBranch and I would like to reference it in the aliases.

1) global config having init.defaultBranch = master
2) global config having alias com = checkout [ init.defaultBranch ]
3) local repos replacing this value e.g. to init.defaultBranch = main
4) using this alias in local repo git com, which will checkout me to
the init.defaultBranch of this repository..

This would allow us to use global aliases independently on the repositories.. If this has not yet been discussed I believe it is the time since many repositories are being customized to the company team/company culture.

Appreciate and thanks, Michal