How to work with submodule in Github


Assume I have 6 repositories in Github A,B,C,x,y,z. They have some complex dependent relations. x is built on A and B. y is built on B and C. And finally, z is built on x and y. The ‘built on’ is realizing by attaching the submodules. We see that if I download code z, it will contain two copies of B because both x and y are using B. When my project becomes larger and larger, I guess there will be lots of reduplicate copies. How to solve this problem?


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