why:
the previous approach was replacing the function-lets in
opcode_impl.nim by the particulate table handlers. the test
functions will verify the the handler functions are sort of
correct but not the assignments in the fork tables.
the handler names of old and new for tables are checked here.
caveat:
verifying tables currently takes a while at compile time.
details:
the op handler table is accessible via op_handlers.nim module
op handler function implementations are found in the op_handlers/
sub-directory
kludge:
for development and pre-testing, any new module can be individually
compiled setting the kludge flag using -d:kludge:1. this causes some
proc/func replacements in turn allowing for omitting imports that would
otherwise cause a circular dependency. otherwise individual compilation
would fail.
in order to prove the overall correctness of the code, the
op_handlers.nim is imported by opcodes_impl.nim when compiling all,
nimbus or test.
