The " with <e1>, <e2>" effects clause was rendered by five verbatim
blocks across the fn / class-method / instance-method / type writers.
Hoisted into write_effects_clause(out, effects); all five sites now
call it. Output is byte-identical — the snapshot/round-trip tests
confirm no drift.
The two forall<...> blocks were left alone: they diverge in the
trailing token (one ends `>`, the other `> ` before a where-clause),
so a shared helper would be awkward rather than cleaner.
Brummel
10da23304e