[CMake] hiding targets from cmake build?

[hex]

In cmake mark_as_advanced will not display variables in any of the cmake 
GUIs unless the show advanced option is on.

I wonder if there is an equivalent for build targets?

I have a bunch of custom_targets custom_a, custom_b, custom_c, ... which 
all depend on custom_all

I don't want all targets to be listed in

cmake --build . --target help


It appears there is a solution for Visual Studio [1] by hiding folders. 
I am using SublimeText, though.

Is there a native solution? Otherwise approximately which steps should I 
take to make a script / plug-in.


[1]: https://stackoverflow.com/a/45918184/10530671