ibc i (IBCImportDir n) f = return f { ibc_importdirs = n : ibc_importdirs f }
ibc i (IBCImportDir n) f = return f { ibc_importdirs = n : ibc_importdirs f }
ibc i (IBCImportDir n) f = return f { ibc_importdirs = n : ibc_importdirs f }