Wilfried
I would beg to disagree with you here. The term "macaronic" also known as "code shifting" is not always used for comic effect. The phenomenon is to be found in every situation where two, or indeed more, languages find themselves co-existing.
At its most crude it consists of merely substituting a word in one language for its equivalent in another. At its most sophisticated, the two languages are interwoven in a structured way both in terms of meter and rhyme. This form of macaronic verse requires a deep knowledge of the languages concerned in both the composer and his audience and betrays a sophistication in language use that has gone unappreciated; the main reason being, in my opinion, that monoglot speakers of the individual languages see this verse form as a "pollution" of their native tradition.
It has a long and honoured history, some of the earliest examples occurring in the Latin-Greek macaronic verse of pre-Christian Rome. The earliest example in a European vernacular is a 6th century Irish poem in Irish and Latin.
Annraoi