転調するときにナチュラルを描かない
\key d \major
a b cis d
\key g \minor
a bes c d
\set Staff.printKeyCancellation = ##f
\key d \major
a b cis d
\key g \minor
a bes c d
a b cis d
\key g \minor
a bes c d
\set Staff.printKeyCancellation = ##f
\key d \major
a b cis d
\key g \minor
a bes c d
