fn check_s7_dispatch(parsed: &ParsedImpl) -> Result<()>Expand description
Validate the S7 dispatch arguments of every S7 instance method: an explicit
s7(dispatch = "..."), and the pair S7 fixes for an Ops / %*%
operator generic (e1, e2 / x, y).
S7 registers a method only when its formals start with the generic’s
dispatch arguments, in order and without defaults, and it rejects the
wrong number of classes in the signature; any violation stops the package
from loading. The generator names the receiver after the first dispatch
argument and takes the others from the method’s leading parameters, so the
rules are checked here, where the error can name the fix. ! is rejected
outright because S7 does not dispatch it. Non-S7 class systems, static
methods and property accessors are a no-op.