rn050.hs:13:7: warning: [-Wdeprecations (in -Wdefault)]
    In the use of ‘op’ (imported from Rn050_A):
    Deprecated: "Use bop instead"

rn050.hs:13:10: warning: [-Wdeprecations (in -Wdefault)]
    In the use of data constructor ‘C’ (imported from Rn050_A):
    Deprecated: "Use D instead"