For public networks, the
eipxxx declarations are of the form (for example):
That is, you declare the transition and the block at which the transition occurred. (Block 4370000 equates to the Byzantium hard fork.)
In the code you can then use
eipxxx in conditionals to execute code-paths that will change after the transitions (by comparing with the current block number).
eip100Transition. Firstly, it's not clear to me that the code for EIP-100 has actually been completed/committed.
eip100Transition isn't used anywhere in either the Parity or Geth codebase.
Secondly, in a private network, which won't have the hard forks that the public network did, there's no need to include the EIP transitions. You can just define the code the behave how you want it to behave. Also, I believe setting the
eipxxx entries to
0 will cause your chain to work as if the transition has already happened. (i.e. The transition "occurred" at block 0, so all subsequent blocks are considered after the transition.)