I didn't see the TV one. I thumbed through the book at a bookstore and wasn't very impressed by it. Special groups have had special terms, and there have been dictionaries of it and songs from the late 16th century. See also Brome's play 'The Beggars Bush', 1641? for examples. English Gypsies still use some of it it. Its called lots of things: thieves jargon, pedlar's French, cant, and so on. I can't remember that term used for it about 15 years ago when describing some Gypsie songs collected in Ireland about 1970.
There are whole books of songs in it in the 18th century- The Scoundrel's Dictionary, The canting Crew, and so on. I forgot what play has Shakespere's song with the burden "Hey the doxie over the dale". Last word is misspelled. Doxie is a virgin beggar lass, a dell isn't, and will probably soon be a mort, then autem-mort of some darkman. On my website I mention 'The Bowman's Prigg's Farewell", but don't have the whole song yet. A farcical esecution of Bowman Prigg. A bowman prig is a pick purse, not a cutpurse. If I remember correctly Chapell's PMOT has "The Budge it is a delicate trade'. J. S. Farmer (with Henley?) put out a whole book of old songs in cant in the late 19th century, but I don't have it or remember its title.